The smb.conf file is a configuration file for the Samba suite. smb.conf contains runtime configuration information for the Samba programs. The complete description of the file format and possible parameters held within are here for reference purposes.
The Samba suite includes a number of different programs. Some of them operate in a client mode, others are server daemons that provide various services to its clients. The smb.conf file is processed in the following way:
To request Samba server daemons to refresh their configuration, please use smbcontrol(1) utility.
The file consists of sections and parameters. A section begins with the name of the section in square brackets and continues until the next section begins. Sections contain parameters of the form:
name = value
The file is line-based - that is, each newline-terminated line represents either a comment, a section name or a parameter.
Section and parameter names are not case sensitive.
Only the first equals sign in a parameter is significant. Whitespace before or after the first equals sign is discarded. Leading, trailing and internal whitespace in section and parameter names is irrelevant. Leading and trailing whitespace in a parameter value is discarded. Internal whitespace within a parameter value is retained verbatim.
Any line beginning with a semicolon (";") or a hash ("#") character is ignored, as are lines containing only whitespace.
Any line ending in a "\" is continued on the next line in the customary UNIX fashion.
The values following the equals sign in parameters are all either a string (no quotes needed) or a boolean, which may be given as yes/no, 1/0 or true/false. Case is not significant in boolean values, but is preserved in string values. Some items such as create masks are numeric.
Each section in the configuration file (except for the [global] section) describes a shared resource (known as a "share"). The section name is the name of the shared resource and the parameters within the section define the shares attributes.
There are three special sections, [global], [homes] and [printers], which are described under special sections. The following notes apply to ordinary section descriptions.
A share consists of a directory to which access is being given plus a description of the access rights which are granted to the user of the service. Some housekeeping options are also specifiable.
Sections are either file share services (used by the client as an extension of their native file systems) or printable services (used by the client to access print services on the host running the server).
Sections may be designated guest services, in which case no password is required to access them. A specified UNIX guest account is used to define access privileges in this case.
Sections other than guest services will require a password to access them. The client provides the username. As older clients only provide passwords and not usernames, you may specify a list of usernames to check against the password using the user = option in the share definition. For modern clients such as Windows 95/98/ME/NT/2000, this should not be necessary.
The access rights granted by the server are masked by the access rights granted to the specified or guest UNIX user by the host system. The server does not grant more access than the host system grants.
The following sample section defines a file space share. The user has write access to the path /home/bar. The share is accessed via the share name foo:
[foo]
m[blue]path = /home/barm[]
m[blue]read only = nom[]
The following sample section defines a printable share. The share is read-only, but printable. That is, the only write access permitted is via calls to open, write to and close a spool file. The guest ok parameter means access will be permitted as the default guest user (specified elsewhere):
[aprinter]
m[blue]path = /usr/spool/publicm[]
m[blue]read only = yesm[]
m[blue]printable = yesm[]
m[blue]guest ok = yesm[]
Parameters in this section apply to the server as a whole, or are defaults for sections that do not specifically define certain items. See the notes under PARAMETERS for more information.
If a section called [homes] is included in the configuration file, services connecting clients to their home directories can be created on the fly by the server.
When the connection request is made, the existing sections are scanned. If a match is found, it is used. If no match is found, the requested section name is treated as a username and looked up in the local password file. If the name exists and the correct password has been given, a share is created by cloning the [homes] section.
Some modifications are then made to the newly created share:
If you decide to use a path = line in your [homes] section, it may be useful to use the %S macro. For example:
path = /data/pchome/%S
is useful if you have different home directories for your PCs than for UNIX access.
This is a fast and simple way to give a large number of clients access to their home directories with a minimum of fuss.
A similar process occurs if the requested section name is "homes", except that the share name is not changed to that of the requesting user. This method of using the [homes] section works well if different users share a client PC.
The [homes] section can specify all the parameters a normal service section can specify, though some make more sense than others. The following is a typical and suitable [homes] section:
[homes] m[blue]read only = nom[]
An important point is that if guest access is specified in the [homes] section, all home directories will be visible to all clients without a password. In the very unlikely event that this is actually desirable, it is wise to also specify read only access.
The browseable flag for auto home directories will be inherited from the global browseable flag, not the [homes] browseable flag. This is useful as it means setting browseable = no in the [homes] section will hide the [homes] share but make any auto home directories visible.
This section works like [homes], but for printers.
If a [printers] section occurs in the configuration file, users are able to connect to any printer specified in the local host's printcap file.
When a connection request is made, the existing sections are scanned. If a match is found, it is used. If no match is found, but a [homes] section exists, it is used as described above. Otherwise, the requested section name is treated as a printer name and the appropriate printcap file is scanned to see if the requested section name is a valid printer share name. If a match is found, a new printer share is created by cloning the [printers] section.
A few modifications are then made to the newly created share:
The [printers] service MUST be printable - if you specify otherwise, the server will refuse to load the configuration file.
Typically the path specified is that of a world-writeable spool directory with the sticky bit set on it. A typical [printers] entry looks like this:
[printers] m[blue]path = /usr/spool/publicm[] m[blue]guest ok = yesm[] m[blue]printable = yesm[]
All aliases given for a printer in the printcap file are legitimate printer names as far as the server is concerned. If your printing subsystem doesn't work like that, you will have to set up a pseudo-printcap. This is a file consisting of one or more lines like this:
alias|alias|alias|alias...
Each alias should be an acceptable printer name for your printing subsystem. In the [global] section, specify the new file as your printcap. The server will only recognize names found in your pseudo-printcap, which of course can contain whatever aliases you like. The same technique could be used simply to limit access to a subset of your local printers.
An alias, by the way, is defined as any component of the first entry of a printcap record. Records are separated by newlines, components (if there are more than one) are separated by vertical bar symbols (|).
On SYSV systems which use lpstat to determine what printers are defined on the system you may be able to use printcap name = lpstat to automatically obtain a list of printers. See the printcap name option for more details.
Starting with Samba version 3.0.23 the capability for non-root users to add, modify, and delete their own share definitions has been added. This capability is called usershares and is controlled by a set of parameters in the [global] section of the smb.conf. The relevant parameters are :
usershare allow guests
usershare max shares
usershare owner only
usershare path
usershare prefix allow list
usershare prefix deny list
usershare template share
To allow members of the UNIX group foo to create user defined shares, create the directory to contain the share definitions as follows:
Become root:
mkdir /usr/local/samba/lib/usershares chgrp foo /usr/local/samba/lib/usershares chmod 1770 /usr/local/samba/lib/usershares
Then add the parameters
m[blue]usershare path = /usr/local/samba/lib/usersharesm[]
m[blue]usershare max shares = 10m[] # (or the desired number of shares)
to the global section of your smb.conf. Members of the group foo may then manipulate the user defined shares using the following commands.
net usershare add sharename path [comment] [acl] [guest_ok=[y|n]]
net usershare delete sharename
net usershare list wildcard-sharename
net usershare info wildcard-sharename
Parameters define the specific attributes of sections.
Some parameters are specific to the [global] section (e.g., security). Some parameters are usable in all sections (e.g., create mask). All others are permissible only in normal sections. For the purposes of the following descriptions the [homes] and [printers] sections will be considered normal. The letter G in parentheses indicates that a parameter is specific to the [global] section. The letter S indicates that a parameter can be specified in a service specific section. All S parameters can also be specified in the [global] section - in which case they will define the default behavior for all services.
Parameters are arranged here in alphabetical order - this may not create best bedfellows, but at least you can find them! Where there are synonyms, the preferred synonym is described, others refer to the preferred synonym.
Many of the strings that are settable in the config file can take substitutions. For example the option "path = /tmp/%u" is interpreted as "path = /tmp/john" if the user connected with the username john.
These substitutions are mostly noted in the descriptions below, but there are some general substitutions which apply whenever they might be relevant. These are:
%U
%G
%h
%m
This parameter is not available when Samba listens on port 445, as clients no longer send this information. If you use this macro in an include statement on a domain that has a Samba domain controller be sure to set in the [global] section smb ports = 139. This will cause Samba to not listen on port 445 and will permit include functionality to function as it did with Samba 2.x.
%L
%M
%R
%d
%a
%I
Before 4.0.0 it could contain IPv4 mapped IPv6 addresses, now it only contains IPv4 or IPv6 addresses.
%J
%i
Before 4.0.0 it could contain IPv4 mapped IPv6 addresses, now it only contains IPv4 or IPv6 addresses.
%j
%T
%t
%D
%w
%$(envvar)
The following substitutes apply only to some configuration options (only those that are used when a connection has been established):
%S
%P
%u
%g
%H
%N
%p
There are some quite creative things that can be done with these substitutions and other smb.conf options.
Samba supports name mangling so that DOS and Windows clients can use files that don't conform to the 8.3 format. It can also be set to adjust the case of 8.3 format filenames.
There are several options that control the way mangling is performed, and they are grouped here rather than listed separately. For the defaults look at the output of the testparm program.
These options can be set separately for each service.
The options are:
case sensitive = yes/no/auto
default case = upper/lower
preserve case = yes/no
short preserve case = yes/no
By default, Samba 3.0 has the same semantics as a Windows NT server, in that it is case insensitive but case preserving. As a special case for directories with large numbers of files, if the case options are set as follows, "case sensitive = yes", "case preserve = no", "short preserve case = no" then the "default case" option will be applied and will modify all filenames sent from the client when accessing this share.
Starting with Samba version 3.2.0, the capability to store Samba configuration in the registry is available. The configuration is stored in the registry key HKLM\Software\Samba\smbconf. There are two levels of registry configuration:
The registry shares are loaded not at startup but on demand at runtime by smbd. Shares defined in smb.conf take priority over shares of the same name defined in registry.
Firstly, a registry only configuration is triggered by setting m[blue]config backend = registrym[] in the [global] section of smb.conf. This resets everything that has been read from config files to this point and reads the content of the global configuration section from the registry. This is the recommended method of using registry based configuration.
Secondly, a mixed configuration can be activated by a special new meaning of the parameter m[blue]include = registrym[] in the [global] section of smb.conf. This reads the global options from registry with the same priorities as for an include of a text file. This may be especially useful in cases where an initial configuration is needed to access the registry.
Activation of global registry options automatically activates registry shares. So in the registry only case, shares are loaded on demand only.
Note: To make registry-based configurations foolproof at least to a certain extent, the use of lock directory and config backend inside the registry configuration has been disabled: Especially by changing the lock directory inside the registry configuration, one would create a broken setup where the daemons do not see the configuration they loaded once it is active.
The registry configuration can be accessed with tools like regedit or net (rpc) registry in the key HKLM\Software\Samba\smbconf. More conveniently, the conf subcommand of the net(8) utility offers a dedicated interface to read and write the registry based configuration locally, i.e. directly accessing the database file, circumventing the server.
In the SMB protocol, users, groups, and machines are represented by their security identifiers (SIDs). On POSIX system Samba processes need to run under corresponding POSIX user identities and with supplemental POSIX groups to allow access to the files owned by those users and groups. The process of mapping SIDs to POSIX users and groups is called IDENTITY MAPPING or, in short, ID MAPPING.
Samba supports multiple ways to map SIDs to POSIX users and groups. The configuration is driven by the m[blue]idmap config DOMAIN : OPTIONm[] option which allows one to specify identity mapping (idmap) options for each domain separately.
Identity mapping modules implement different strategies for mapping of SIDs to POSIX user and group identities. They are applicable to different use cases and scenarios. It is advised to read the documentation of the individual identity mapping modules before choosing a specific scenario to use. Each identity management module is documented in a separate manual page. The standard idmap backends are tdb (idmap_tdb(8)), tdb2 (idmap_tdb2(8)), ldap (idmap_ldap(8)), rid (idmap_rid(8)), hash (idmap_hash(8)), autorid (idmap_autorid(8)), ad (idmap_ad(8)), nss (idmap_nss(8)), and rfc2307 (idmap_rfc2307(8)).
Overall, ID mapping configuration should be decided carefully. Changes to the already deployed ID mapping configuration may create the risk of losing access to the data or disclosing the data to the wrong parties.
This example shows how to configure two domains with idmap_rid(8), the principal domain and a trusted domain, leaving the default id mapping scheme at tdb.
[global]
security = domain
workgroup = MAIN
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999
idmap config MAIN : backend = rid
idmap config MAIN : range = 5000000-5999999
idmap config TRUSTED : backend = rid
idmap config TRUSTED : range = 6000000-6999999
abort shutdown script (G)
If the connected user possesses the SeRemoteShutdownPrivilege, right, this command will be run as root.
Default: abort shutdown script = ""
Example: abort shutdown script = /sbin/shutdown -c
access based share enum (S)
Default: access based share enum = no
acl allow execute always (S)
If this parameter is set to "True", Samba does not check execute permissions on "open for execution", thus re-establishing the behaviour of Samba 3.6. This can be useful to smoothen upgrades from older Samba versions to 4.0 and newer. This setting is not meant to be used as a permanent setting, but as a temporary relief: It is recommended to fix the permissions in the ACLs and reset this parameter to the default after a certain transition period.
Default: acl allow execute always = no
acl check permissions (S)
This boolean parameter controls what smbd(8) does on receiving a protocol request of "open for delete" from a Windows client. If a Windows client doesn't have permissions to delete a file then they expect this to be denied at open time. POSIX systems normally only detect restrictions on delete by actually attempting to delete the file or directory. As Windows clients can (and do) "back out" a delete request by unsetting the "delete on close" bit Samba cannot delete the file immediately on "open for delete" request as we cannot restore such a deleted file. With this parameter set to true (the default) then smbd checks the file system permissions directly on "open for delete" and denies the request without actually deleting the file if the file system permissions would seem to deny it. This is not perfect, as it's possible a user could have deleted a file without Samba being able to check the permissions correctly, but it is close enough to Windows semantics for mostly correct behaviour. Samba will correctly check POSIX ACL semantics in this case.
If this parameter is set to "false" Samba doesn't check permissions on "open for delete" and allows the open. If the user doesn't have permission to delete the file this will only be discovered at close time, which is too late for the Windows user tools to display an error message to the user. The symptom of this is files that appear to have been deleted "magically" re-appearing on a Windows explorer refresh. This is an extremely advanced protocol option which should not need to be changed. This parameter was introduced in its final form in 3.0.21, an earlier version with slightly different semantics was introduced in 3.0.20. That older version is not documented here.
Default: acl check permissions = yes
acl group control (S)
On a Windows server, groups may be the owner of a file or directory - thus allowing anyone in that group to modify the permissions on it. This allows the delegation of security controls on a point in the filesystem to the group owner of a directory and anything below it also owned by that group. This means there are multiple people with permissions to modify ACLs on a file or directory, easing manageability.
This parameter allows Samba to also permit delegation of the control over a point in the exported directory hierarchy in much the same way as Windows. This allows all members of a UNIX group to control the permissions on a file or directory they have group ownership on.
This parameter is best used with the m[blue]inherit ownerm[] option and also on a share containing directories with the UNIX setgid bit set on them, which causes new files and directories created within it to inherit the group ownership from the containing directory.
This parameter was deprecated in Samba 3.0.23, but re-activated in Samba 3.0.31 and above, as it now only controls permission changes if the user is in the owning primary group. It is now no longer equivalent to the dos filemode option.
Default: acl group control = no
acl map full control (S)
Default: acl map full control = yes
add group script (G)
Default: add group script =
Example: add group script = /usr/sbin/groupadd %g
additional dns hostnames (G)
Default: additional dns hostnames = # empty string (no additional dns names)
Example: additional dns hostnames = host2.example.com host3.other.com
add machine script (G)
This option is very similar to the m[blue]add user scriptm[], and likewise uses the %u substitution for the account name. Do not use the %m substitution.
Default: add machine script =
Example: add machine script = /usr/sbin/adduser -n -g machines -c Machine -d /var/lib/nobody -s /bin/false %u
addport command (G)
Default: addport command =
Example: addport command = /etc/samba/scripts/addport.sh
addprinter command (G)
For a Samba host this means that the printer must be physically added to the underlying printing system. The addprinter command defines a script to be run which will perform the necessary operations for adding the printer to the print system and to add the appropriate service definition to the smb.conf file in order that it can be shared by smbd(8).
The addprinter command is automatically invoked with the following parameter (in order):
Once the addprinter command has been executed, smbd will reparse the smb.conf to determine if the share defined by the APW exists. If the sharename is still invalid, then smbd will return an ACCESS_DENIED error to the client.
The addprinter command program can output a single line of text, which Samba will set as the port the new printer is connected to. If this line isn't output, Samba won't reload its printer shares.
Default: addprinter command =
Example: addprinter command = /usr/bin/addprinter
add share command (G)
In order to successfully execute the add share command, smbd requires that the administrator connects using a root account (i.e. uid == 0) or has the SeDiskOperatorPrivilege. Scripts defined in the add share command parameter are executed as root.
When executed, smbd will automatically invoke the add share command with five parameters.
Default: add share command =
Example: add share command = /usr/local/bin/addshare
add user script (G)
Normally, a Samba server requires that UNIX users are created for all users accessing files on this server. For sites that use Windows NT account databases as their primary user database creating these users and keeping the user list in sync with the Windows NT PDC is an onerous task. This option allows smbd to create the required UNIX users ON DEMAND when a user accesses the Samba server.
When the Windows user attempts to access the Samba server, at login (session setup in the SMB protocol) time, smbd(8) contacts the m[blue]password serverm[] and attempts to authenticate the given user with the given password. If the authentication succeeds then smbd attempts to find a UNIX user in the UNIX password database to map the Windows user into. If this lookup fails, and m[blue]add user scriptm[] is set then smbd will call the specified script AS ROOT, expanding any %u argument to be the user name to create.
If this script successfully creates the user then smbd will continue on as though the UNIX user already existed. In this way, UNIX users are dynamically created to match existing Windows NT accounts.
See also m[blue]securitym[], m[blue]password serverm[], m[blue]delete user scriptm[].
Default: add user script =
Example: add user script = /usr/local/samba/bin/add_user %u
add user to group script (G)
Note that the adduser command used in the example below does not support the used syntax on all systems.
Default: add user to group script =
Example: add user to group script = /usr/sbin/adduser %u %g
administrative share (S)
See the section below on m[blue]securitym[] for more information about this option.
Default: administrative share = no
admin users (S)
You should use this option very carefully, as any user in this list will be able to do anything they like on the share, irrespective of file permissions.
Default: admin users =
Example: admin users = jason
afs share (S)
Default: afs share = no
afs token lifetime (G)
Set this parameter to 0 to get NEVERDATE.
Default: afs token lifetime = 604800
afs username map (G)
The mapped user name must contain the cell name to log into, so without setting this parameter there will be no token.
Default: afs username map =
Example: afs username map = %u@afs.samba.org
aio max threads (G)
Related command: m[blue]aio read sizem[]
Related command: m[blue]aio write sizem[]
Default: aio max threads = 100
aio read size (S)
The only reasonable values for this parameter are 0 (no async I/O) and 1 (always do async I/O).
Related command: m[blue]write cache sizem[]
Related command: m[blue]aio write sizem[]
Default: aio read size = 1
Example: aio read size = 0 # Always do reads synchronously
aio write behind (S)
The syntax is identical to the m[blue]veto filesm[] parameter.
Default: aio write behind =
Example: aio write behind = /*.tmp/
aio write size (S)
The only reasonable values for this parameter are 0 (no async I/O) and 1 (always do async I/O).
Compared to m[blue]aio read sizem[] this parameter has a smaller effect, most writes should end up in the file system cache. Writes that require space allocation might benefit most from going asynchronous.
Related command: m[blue]write cache sizem[]
Related command: m[blue]aio read sizem[]
Default: aio write size = 1
Example: aio write size = 0 # Always do writes synchronously
algorithmic rid base (G)
Setting this option to a larger value could be useful to sites transitioning from WinNT and Win2k, as existing user and group rids would otherwise clash with system users etc.
All UIDs and GIDs must be able to be resolved into SIDs for the correct operation of ACLs on the server. As such the algorithmic mapping can't be 'turned off', but pushing it 'out of the way' should resolve the issues. Users and groups can then be assigned 'low' RIDs in arbitrary-rid supporting backends.
Default: algorithmic rid base = 1000
Example: algorithmic rid base = 100000
allocation roundup size (S)
This parameter is deprecated and will be removed in one of the next Samba releases.
The integer parameter specifies the roundup size in bytes.
Default: allocation roundup size = 0
Example: allocation roundup size = 1048576 # (to set it to the former default of 1 MiB)
allow dcerpc auth level connect (G)
Some interfaces like samr, lsarpc and netlogon have a hard-coded default of no and epmapper, mgmt and rpcecho have a hard-coded default of yes.
The behavior can be overwritten per interface name (e.g. lsarpc, netlogon, samr, srvsvc, winreg, wkssvc ...) by using 'allow dcerpc auth level connect:interface = yes' as option.
This option yields precedence to the implementation specific restrictions. E.g. the drsuapi and backupkey protocols require DCERPC_AUTH_LEVEL_PRIVACY. The dnsserver protocol requires DCERPC_AUTH_LEVEL_INTEGRITY.
Default: allow dcerpc auth level connect = no
Example: allow dcerpc auth level connect = yes
allow dns updates (G)
DNS updates can either be disallowed completely by setting it to disabled, enabled over secure connections only by setting it to secure only or allowed in all cases by setting it to nonsecure.
Default: allow dns updates = secure only
Example: allow dns updates = disabled
allow insecure wide links (G)
Setting m[blue]allow insecure wide linksm[] to true disables the link between these two parameters, removing this protection and allowing a site to configure the server to follow symlinks (by setting m[blue]wide linksm[] to "true") even when m[blue]unix extensionsm[] is turned on.
It is not recommended to enable this option unless you fully understand the implications of allowing the server to follow symbolic links created by UNIX clients. For most normal Samba configurations this would be considered a security hole and setting this parameter is not recommended.
This option was added at the request of sites who had deliberately set Samba up in this way and needed to continue supporting this functionality without having to patch the Samba code.
Default: allow insecure wide links = no
allow nt4 crypto (G)
This option was added with Samba 4.2.0. It may lock out clients which worked fine with Samba versions up to 4.1.x. as the effective default was "yes" there, while it is "no" now.
If you have clients without RequireStrongKey = 1 in the registry, you may need to set "allow nt4 crypto = yes", until you have fixed all clients.
"allow nt4 crypto = yes" allows weak crypto to be negotiated, maybe via downgrade attacks.
This option yields precedence to the 'reject md5 clients' option.
Default: allow nt4 crypto = no
allow trusted domains (G)
This is useful if you only want your Samba server to serve resources to users in the domain it is a member of. As an example, suppose that there are two domains DOMA and DOMB. DOMB is trusted by DOMA, which contains the Samba server. Under normal circumstances, a user with an account in DOMB can then access the resources of a UNIX account with the same account name on the Samba server even if they do not have an account in DOMA. This can make implementing a security boundary difficult.
Default: allow trusted domains = yes
allow unsafe cluster upgrade (G)
Default: allow unsafe cluster upgrade = no
apply group policies (G)
Default: apply group policies = no
Example: apply group policies = yes
async dns timeout (G)
The minimum value of this parameter is clamped at 1 second.
Default: async dns timeout = 10
Example: async dns timeout = 20
async smb echo handler (G)
Default: async smb echo handler = no
auth event notification (G)
This should be considered a developer option (it assists in the Samba testsuite) rather than a facility for external auditing, as message delivery is not guaranteed (a feature that the testsuite works around). Additionally Samba must be compiled with the jansson support for this option to be effective.
The authentication events are also logged via the normal logging methods when the m[blue]log levelm[] is set appropriately.
Default: auth event notification = no
preload
auto services (G)
Note that if you just want all printers in your printcap file loaded then the m[blue]load printersm[] option is easier.
Default: auto services =
Example: auto services = fred lp colorlp
available (S)
Default: available = yes
bind dns directory
binddns dir (G)
Default: binddns dir = /var/lib/samba/bind-dns
bind interfaces only (G)
For name service it causes nmbd to bind to ports 137 and 138 on the interfaces listed in the m[blue]interfacesm[] parameter. nmbd also binds to the "all addresses" interface (0.0.0.0) on ports 137 and 138 for the purposes of reading broadcast messages. If this option is not set then nmbd will service name requests on all of these sockets. If m[blue]bind interfaces onlym[] is set then nmbd will check the source address of any packets coming in on the broadcast sockets and discard any that don't match the broadcast addresses of the interfaces in the m[blue]interfacesm[] parameter list. As unicast packets are received on the other sockets it allows nmbd to refuse to serve names to machines that send packets that arrive through any interfaces not listed in the m[blue]interfacesm[] list. IP Source address spoofing does defeat this simple check, however, so it must not be used seriously as a security feature for nmbd.
For file service it causes smbd(8) to bind only to the interface list given in the m[blue]interfacesm[] parameter. This restricts the networks that smbd will serve, to packets coming in on those interfaces. Note that you should not use this parameter for machines that are serving PPP or other intermittent or non-broadcast network interfaces as it will not cope with non-permanent interfaces.
If m[blue]bind interfaces onlym[] is set and the network address 127.0.0.1 is not added to the m[blue]interfacesm[] parameter list smbpasswd(8) may not work as expected due to the reasons covered below.
To change a users SMB password, the smbpasswd by default connects to the localhost - 127.0.0.1 address as an SMB client to issue the password change request. If m[blue]bind interfaces onlym[] is set then unless the network address 127.0.0.1 is added to the m[blue]interfacesm[] parameter list then smbpasswd will fail to connect in it's default mode. smbpasswd can be forced to use the primary IP interface of the local host by using its smbpasswd(8) -r remote machine parameter, with remote machine set to the IP name of the primary interface of the local host.
Default: bind interfaces only = no
blocking locks (S)
If this parameter is set and the lock range requested cannot be immediately satisfied, samba will internally queue the lock request, and periodically attempt to obtain the lock until the timeout period expires.
If this parameter is set to no, then samba will behave as previous versions of Samba would and will fail the lock request immediately if the lock range cannot be obtained.
Default: blocking locks = yes
block size (S)
Changing this parameter may have some effect on the efficiency of client writes, this is not yet confirmed. This parameter was added to allow advanced administrators to change it (usually to a higher value) and test the effect it has on client write performance without re-compiling the code. As this is an experimental option it may be removed in a future release.
Changing this option does not change the disk free reporting size, just the block size unit reported to the client.
Default: block size = 1024
Example: block size = 4096
browsable
browseable (S)
Default: browseable = yes
browse list (G)
Default: browse list = yes
cache directory (G)
This option specifies the directory for storing TDB files containing non-persistent data that will be kept across service restarts. The directory should be placed on persistent storage, but the data can be safely deleted by an administrator.
Default: cache directory = /var/lib/samba
Example: cache directory = /var/run/samba/locks/cache
casesignames
case sensitive (S)
Default: case sensitive = auto
change notify (G)
You should never need to change this parameter
Default: change notify = yes
change share command (G)
In order to successfully execute the change share command, smbd requires that the administrator connects using a root account (i.e. uid == 0) or has the SeDiskOperatorPrivilege. Scripts defined in the change share command parameter are executed as root.
When executed, smbd will automatically invoke the change share command with six parameters.
Default: change share command =
Example: change share command = /usr/local/bin/changeshare
check parent directory delete on close (S)
Default: check parent directory delete on close = no
check password script (G)
The program must return 0 on a good password, or any other value if the password is bad. In case the password is considered weak (the program does not return 0) the user will be notified and the password change will fail.
In Samba AD, this script will be run AS ROOT by samba(8) without any substitutions.
Note that starting with Samba 4.11 the following environment variables are exported to the script:
Default: check password script = # Disabled
Example: check password script = /usr/local/sbin/crackcheck
cldap port (G)
Default: cldap port = 389
Example: cldap port = 3389
client ipc max protocol (G)
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol.
The value default refers to the latest supported protocol, currently SMB3_11.
See m[blue]client max protocolm[] for a full list of available protocols. The values CORE, COREPLUS, LANMAN1, LANMAN2 are silently upgraded to NT1.
Default: client ipc max protocol = default
Example: client ipc max protocol = SMB2_10
client ipc min protocol (G)
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol.
The value default refers to the higher value of NT1 and the effective value of m[blue]client min protocolm[].
See m[blue]client max protocolm[] for a full list of available protocols. The values CORE, COREPLUS, LANMAN1, LANMAN2 are silently upgraded to NT1.
Default: client ipc min protocol = default
Example: client ipc min protocol = SMB3_11
client ipc signing (G)
When set to mandatory or default, SMB signing is required.
When set to auto, SMB signing is offered, but not enforced and if set to disabled, SMB signing is not offered either.
Connections from winbindd to Active Directory Domain Controllers always enforce signing.
Default: client ipc signing = default
client lanman auth (G)
That is, in the future, the current default of client NTLMv2 auth = yes will be the enforced behaviour.
This parameter determines whether or not smbclient(8) and other samba client tools will attempt to authenticate itself to servers using the weaker LANMAN password hash. If disabled, only server which support NT password hashes (e.g. Windows NT/2000, Samba, etc... but not Windows 95/98) will be able to be connected from the Samba client.
The LANMAN encrypted response is easily broken, due to its case-insensitive nature, and the choice of algorithm. Clients without Windows 95/98 servers are advised to disable this option.
Disabling this option will also disable the client plaintext auth option.
Likewise, if the client ntlmv2 auth parameter is enabled, then only NTLMv2 logins will be attempted.
Default: client lanman auth = no
client ldap sasl wrapping (G)
The values sign and seal are only available if Samba has been compiled against a modern OpenLDAP version (2.3.x or higher).
This option is needed in the case of Domain Controllers enforcing the usage of signed LDAP connections (e.g. Windows 2000 SP3 or higher). LDAP sign and seal can be controlled with the registry key "HKLM\System\CurrentControlSet\Services\ NTDS\Parameters\LDAPServerIntegrity" on the Windows server side.
Depending on the used KRB5 library (MIT and older Heimdal versions) it is possible that the message "integrity only" is not supported. In this case, sign is just an alias for seal.
The default value is sign. That implies synchronizing the time with the KDC in the case of using Kerberos.
Default: client ldap sasl wrapping = sign
client max protocol (G)
Possible values are :
The value default refers to SMB3_11.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the m[blue]client ipc max protocolm[] option.
Default: client max protocol = default
Example: client max protocol = LANMAN1
client min protocol (G)
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol unless you connect to a legacy SMB1-only server.
See Related command: m[blue]client max protocolm[] for a full list of available protocols.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the m[blue]client ipc min protocolm[] option.
Note that most command line tools support --option='client min protocol=NT1', so it may not be required to enable SMB1 protocols globally in smb.conf.
Default: client min protocol = SMB2_02
Example: client min protocol = NT1
client NTLMv2 auth (G)
That is, in the future, the current default of client NTLMv2 auth = yes will be the enforced behaviour.
This parameter determines whether or not smbclient(8) will attempt to authenticate itself to servers using the NTLMv2 encrypted password response.
If enabled, only an NTLMv2 and LMv2 response (both much more secure than earlier versions) will be sent. Older servers (including NT4 < SP4, Win9x and Samba 2.2) are not compatible with NTLMv2 when not in an NTLMv2 supporting domain
Similarly, if enabled, NTLMv1, client lanman auth and client plaintext auth authentication will be disabled. This also disables share-level authentication.
If disabled, an NTLM response (and possibly a LANMAN response) will be sent by the client, depending on the value of client lanman auth.
Note that Windows Vista and later versions already use NTLMv2 by default, and some sites (particularly those following 'best practice' security polices) only allow NTLMv2 responses, and not the weaker LM or NTLM.
When m[blue]client use spnegom[] is also set to yes extended security (SPNEGO) is required in order to use NTLMv2 only within NTLMSSP. This behavior was introduced with the patches for CVE-2016-2111.
Default: client NTLMv2 auth = yes
client plaintext auth (G)
That is, in the future, the current default of client plaintext auth = no will be the enforced behaviour.
Specifies whether a client should send a plaintext password if the server does not support encrypted passwords.
Default: client plaintext auth = no
client schannel (G)
This controls whether the client offers or even demands the use of the netlogon schannel. m[blue]client schannel = nom[] does not offer the schannel, m[blue]client schannel = autom[] offers the schannel but does not enforce it, and m[blue]client schannel = yesm[] denies access if the server is not able to speak netlogon schannel.
Note that for active directory domains this is hardcoded to m[blue]client schannel = yesm[].
This option yields precedence to the m[blue]require strong keym[] option.
Default: client schannel = yes
Example: client schannel = auto
client signing (G)
When set to auto or default, SMB signing is offered, but not enforced.
When set to mandatory, SMB signing is required and if set to disabled, SMB signing is not offered either.
IPC$ connections for DCERPC e.g. in winbindd, are handled by the m[blue]client ipc signingm[] option.
Default: client signing = default
client smb encrypt (G)
Effects for SMB1
When set to default, SMB encryption is probed, but not enforced. When set to required, SMB encryption is required and if set to disabled, SMB encryption can not be negotiated.
Effects for SMB3 and newer
These features can be controlled with settings of client smb encrypt as follows:
Default: client smb encrypt = default
client use spnego principal (G)
If enabled, Samba can attempt to use Kerberos to contact servers known only by IP address. Kerberos relies on names, so ordinarily cannot function in this situation.
This is a VERY BAD IDEA for security reasons, and so this parameter SHOULD NOT BE USED. It will be removed in a future version of Samba.
If disabled, Samba will use the name used to look up the server when asking the KDC for a ticket. This avoids situations where a server may impersonate another, soliciting authentication as one principal while being known on the network as another.
Note that Windows XP SP2 and later versions already follow this behaviour, and Windows Vista and later servers no longer supply this 'rfc4178 hint' principal on the server side.
This parameter is deprecated in Samba 4.2.1 and will be removed (along with the functionality) in a later release of Samba.
Default: client use spnego principal = no
client use spnego (G)
That is, in the future, the current default of client use spnego = yes will be the enforced behaviour.
This variable controls whether Samba clients will try to use Simple and Protected NEGOciation (as specified by rfc2478) with supporting servers (including WindowsXP, Windows2000 and Samba 3.0) to agree upon an authentication mechanism. This enables Kerberos authentication in particular.
When m[blue]client NTLMv2 authm[] is also set to yes extended security (SPNEGO) is required in order to use NTLMv2 only within NTLMSSP. This behavior was introduced with the patches for CVE-2016-2111.
Default: client use spnego = yes
cluster addresses (G)
Default: cluster addresses =
Example: cluster addresses = 10.0.0.1 10.0.0.2 10.0.0.3
clustering (G)
Set this parameter to yes only if you have a cluster setup with ctdb running.
Default: clustering = no
comment (S)
If you want to set the string that is displayed next to the machine name then see the m[blue]server stringm[] parameter.
Default: comment = # No comment
Example: comment = Fred's Files
config backend (G)
Note: This option can not be set inside the registry configuration itself.
Default: config backend = file
Example: config backend = registry
config file (G)
For this reason, if the name of the config file has changed when the parameters are loaded then it will reload them from the new config file.
This option takes the usual substitutions, which can be very useful.
If the config file doesn't exist then it won't be loaded (allowing you to special case the config files of just a few clients).
No default
Example: config file = /usr/local/samba/lib/smb.conf.%m
copy (S)
This feature lets you set up a 'template' service and create similar services easily. Note that the service being copied must occur earlier in the configuration file than the service doing the copying.
Default: copy =
Example: copy = otherservice
create krb5 conf (G)
Preventing winbind from doing this might become necessary if you have to add special options into your system-krb5.conf that winbind does not see.
Default: create krb5 conf = yes
create mode
create mask (S)
The default value of this parameter removes the group and other write and execute bits from the UNIX modes.
Following this Samba will bit-wise 'OR' the UNIX mode created from this parameter with the value of the m[blue]force create modem[] parameter which is set to 000 by default.
This parameter does not affect directory masks. See the parameter m[blue]directory maskm[] for details.
Default: create mask = 0744
Example: create mask = 0775
csc policy (S)
These values correspond to those used on Windows servers.
For example, shares containing roaming profiles can have offline caching disabled using m[blue]csc policy = disablem[].
Default: csc policy = manual
Example: csc policy = programs
ctdbd socket (G)
Default: ctdbd socket =
Example: ctdbd socket = /tmp/ctdb.socket
ctdb locktime warn threshold (G)
The default value of 0 disables this logging.
Default: ctdb locktime warn threshold = 0
ctdb timeout (G)
When something in the cluster blocks, it can happen that we wait indefinitely long for ctdb, just adding to the blocking condition. In a well-running cluster this should never happen, but there are too many components in a cluster that might have hickups. Choosing the right balance for this value is very tricky, because on a busy cluster long service times to transfer something across the cluster might be valid. Setting it too short will degrade the service your cluster presents, setting it too long might make the cluster itself not recover from something severely broken for too long.
Be aware that if you set this parameter, this needs to be in the file smb.conf, it is not really helpful to put this into a registry configuration (typical on a cluster), because to access the registry contact to ctdb is required.
Setting ctdb timeout to n makes any process waiting longer than n milliseconds for a reply by the cluster panic. Setting it to 0 (the default) makes Samba block forever, which is the highly recommended default.
Default: ctdb timeout = 0
cups connection timeout (G)
If set, this option specifies the number of seconds that smbd will wait whilst trying to contact to the CUPS server. The connection will fail if it takes longer than this number of seconds.
Default: cups connection timeout = 30
Example: cups connection timeout = 60
cups encrypt (G)
When set to auto we will try to do a TLS handshake on each CUPS connection setup. If that fails, we will fall back to unencrypted operation.
Default: cups encrypt = no
cups options (S)
You can pass any generic print option known to CUPS (as listed in the CUPS "Software Users' Manual"). You can also pass any printer specific option (as listed in "lpoptions -d printername -l") valid for the target queue. Multiple parameters should be space-delimited name/value pairs according to the PAPI text option ABNF specification. Collection values ("name={a=... b=... c=...}") are stored with the curley brackets intact.
You should set this parameter to raw if your CUPS server error_log file contains messages such as "Unsupported format 'application/octet-stream'" when printing from a Windows client through Samba. It is no longer necessary to enable system wide raw printing in /etc/cups/mime.{convs,types}.
Default: cups options = ""
Example: cups options = "raw media=a4"
cups server (G)
If set, this option overrides the ServerName option in the CUPS client.conf. This is necessary if you have virtual samba servers that connect to different CUPS daemons.
Optionally, a port can be specified by separating the server name and port number with a colon. If no port was specified, the default port for IPP (631) will be used.
Default: cups server = ""
Example: cups server = mycupsserver
Example: cups server = mycupsserver:1631
dcerpc endpoint servers (G)
Default: dcerpc endpoint servers = epmapper, wkssvc, rpcecho, samr, netlogon, lsarpc, drsuapi, dssetup, unixinfo, browser, eventlog6, backupkey, dnsserver
Example: dcerpc endpoint servers = rpcecho
deadtime (G)
This is useful to stop a server's resources being exhausted by a large number of inactive connections.
Most clients have an auto-reconnect feature when a connection is broken so in most cases this parameter should be transparent to users.
Using this parameter with a timeout of a few minutes is recommended for most systems.
A deadtime of zero indicates that no auto-disconnection should be performed.
Default: deadtime = 10080
Example: deadtime = 15
debug class (G)
For more information about currently available debug classes, see section about m[blue]log levelm[].
Default: debug class = no
debug encryption (G)
Warning: access to these values enables the decryption of any encrypted traffic on the dumped sessions. This option should only be enabled for debugging purposes.
Default: debug encryption = no
debug hires timestamp (G)
Note that the parameter m[blue]debug timestampm[] must be on for this to have an effect.
Default: debug hires timestamp = yes
debug pid (G)
Note that the parameter m[blue]debug timestampm[] must be on for this to have an effect.
Default: debug pid = no
debug prefix timestamp (G)
Note that this parameter overrides the m[blue]debug timestampm[] parameter.
Default: debug prefix timestamp = no
debug uid (G)
Note that the parameter m[blue]debug timestampm[] must be on for this to have an effect.
Default: debug uid = no
dedicated keytab file (G)
Default: dedicated keytab file =
Example: dedicated keytab file = /usr/local/etc/krb5.keytab
default case (S)
Default: default case = lower
default devmode (S)
Most problems with serving printer drivers to Windows NT/2k/XP clients can be traced to a problem with the generated device mode. Certain drivers will do things such as crashing the client's Explorer.exe with a NULL devmode. However, other printer drivers can cause the client's spooler service (spoolsv.exe) to die if the devmode was not created by the driver itself (i.e. smbd generates a default devmode).
This parameter should be used with care and tested with the printer driver in question. It is better to leave the device mode to NULL and let the Windows client set the correct values. Because drivers do not do this all the time, setting default devmode = yes will instruct smbd to generate a default one.
For more information on Windows NT/2k printing and Device Modes, see the MSDN documentation.
Default: default devmode = yes
default
default service (G)
There is no default value for this parameter. If this parameter is not given, attempting to connect to a nonexistent service results in an error.
Typically the default service would be a m[blue]guest okm[], m[blue]read-onlym[] service.
Also note that the apparent service name will be changed to equal that of the requested service, this is very useful as it allows you to use macros like %S to make a wildcard service.
Note also that any "_" characters in the name of the service used in the default service will get mapped to a "/". This allows for interesting things.
Default: default service =
Example: default service = pub
defer sharing violations (G)
UNIX by default does not have this behaviour.
There should be no reason to turn off this parameter, as it is designed to enable Samba to more correctly emulate Windows.
Default: defer sharing violations = yes
delete group script (G)
Default: delete group script =
deleteprinter command (G)
For a Samba host this means that the printer must be physically deleted from the underlying printing system. The m[blue]deleteprinter commandm[] defines a script to be run which will perform the necessary operations for removing the printer from the print system and from smb.conf.
The m[blue]deleteprinter commandm[] is automatically called with only one parameter: m[blue]printer namem[].
Once the m[blue]deleteprinter commandm[] has been executed, smbd will reparse the smb.conf to check that the associated printer no longer exists. If the sharename is still valid, then smbd will return an ACCESS_DENIED error to the client.
Default: deleteprinter command =
Example: deleteprinter command = /usr/bin/removeprinter
delete readonly (S)
This option may be useful for running applications such as rcs, where UNIX file ownership prevents changing file permissions, and DOS semantics prevent deletion of a read only file.
Default: delete readonly = no
delete share command (G)
In order to successfully execute the delete share command, smbd requires that the administrator connects using a root account (i.e. uid == 0) or has the SeDiskOperatorPrivilege. Scripts defined in the delete share command parameter are executed as root.
When executed, smbd will automatically invoke the delete share command with two parameters.
Default: delete share command =
Example: delete share command = /usr/local/bin/delshare
delete user from group script (G)
Default: delete user from group script =
Example: delete user from group script = /usr/sbin/deluser %u %g
delete user script (G)
This script is called when a remote client removes a user from the server, normally using 'User Manager for Domains' or rpcclient.
This script should delete the given UNIX username.
Default: delete user script =
Example: delete user script = /usr/local/samba/bin/del_user %u
delete veto files (S)
If this option is set to yes, then Samba will attempt to recursively delete any files and directories within the vetoed directory. This can be useful for integration with file serving systems such as NetAtalk which create meta-files within directories you might normally veto DOS/Windows users from seeing (e.g. .AppleDouble)
Setting m[blue]delete veto files = yesm[] allows these directories to be transparently deleted when the parent directory is deleted (so long as the user has permissions to do so).
Default: delete veto files = no
dfree cache time (S)
This is a new parameter introduced in Samba version 3.0.21. It specifies in seconds the time that smbd will cache the output of a disk free query. If set to zero (the default) no caching is done. This allows a heavily loaded server to prevent rapid spawning of m[blue]dfree commandm[] scripts increasing the load.
By default this parameter is zero, meaning no caching will be done.
No default
Example: dfree cache time = 60
dfree command (S)
This setting allows the replacement of the internal routines to calculate the total disk space and amount available with an external routine. The example below gives a possible script that might fulfill this function.
In Samba version 3.0.21 this parameter has been changed to be a per-share parameter, and in addition the parameter m[blue]dfree cache timem[] was added to allow the output of this script to be cached for systems under heavy load.
The external program will be passed a single parameter indicating a directory in the filesystem being queried. This will typically consist of the string ./. The script should return two integers in ASCII. The first should be the total disk space in blocks, and the second should be the number of available blocks. An optional third return value can give the block size in bytes. The default blocksize is 1024 bytes.
Note: Your script should NOT be setuid or setgid and should be owned by (and writeable only by) root!
Where the script dfree (which must be made executable) could be:
#!/bin/sh
df "$1" | tail -1 | awk '{print $(NF-4),$(NF-2)}'
or perhaps (on Sys V based systems):
#!/bin/sh
/usr/bin/df -k "$1" | tail -1 | awk '{print $3" "$5}'
Note that you may have to replace the command names with full path names on some systems. Also note the arguments passed into the script should be quoted inside the script in case they contain special characters such as spaces or newlines.
By default internal routines for determining the disk capacity and remaining space will be used.
No default
Example: dfree command = /usr/local/samba/bin/dfree
dgram port (G)
Default: dgram port = 138
directory mode
directory mask (S)
When a directory is created, the necessary permissions are calculated according to the mapping from DOS modes to UNIX permissions, and the resulting UNIX mode is then bit-wise 'AND'ed with this parameter. This parameter may be thought of as a bit-wise MASK for the UNIX modes of a directory. Any bit not set here will be removed from the modes set on a directory when it is created.
The default value of this parameter removes the 'group' and 'other' write bits from the UNIX mode, allowing only the user who owns the directory to modify it.
Following this Samba will bit-wise 'OR' the UNIX mode created from this parameter with the value of the m[blue]force directory modem[] parameter. This parameter is set to 000 by default (i.e. no extra mode bits are added).
Default: directory mask = 0755
Example: directory mask = 0775
directory name cache size (S)
Default: directory name cache size = 100
directory security mask (S)
No default
disable netbios (G)
disable spoolss (G)
Default: disable spoolss = no
dmapi support (S)
Note that Samba infers the status of a file by examining the events that a DMAPI application has registered interest in. This heuristic is satisfactory for a number of hierarchical storage systems, but there may be system for which it will fail. In this case, Samba may erroneously report files to be offline.
This parameter is only available if a supported DMAPI implementation was found at compilation time. It will only be used if DMAPI is found to enabled on the system at run time.
Default: dmapi support = no
dns forwarder (G)
The DNS forwarder is only used if the internal DNS server in Samba is used.
Default: dns forwarder =
Example: dns forwarder = 192.168.0.1 192.168.0.2
dns proxy (G)
Note that the maximum length for a NetBIOS name is 15 characters, so the DNS name (or DNS alias) can likewise only be 15 characters, maximum.
nmbd spawns a second copy of itself to do the DNS name lookup requests, as doing a name lookup is a blocking action.
Default: dns proxy = yes
dns update command (G)
Default: dns update command = /builddir/build/BUILD/samba-4.14.2/source4/scripting/bin/samba_dnsupdate
Example: dns update command = /usr/local/sbin/dnsupdate
dns zone scavenging (G)
domain logons (G)
That is, in the future, the current default of domain logons = no will be the enforced behaviour.
If set to yes, the Samba server will provide the netlogon service for Windows 9X network logons for the m[blue]workgroupm[] it is in. This will also cause the Samba server to act as a domain controller for NT4 style domain services. For more details on setting up this feature see the Domain Control chapter of the Samba HOWTO Collection.
Default: domain logons = no
domain master (G)
Note that Windows NT Primary Domain Controllers expect to be able to claim this m[blue]workgroupm[] specific special NetBIOS name that identifies them as domain master browsers for that m[blue]workgroupm[] by default (i.e. there is no way to prevent a Windows NT PDC from attempting to do this). This means that if this parameter is set and nmbd claims the special name for a m[blue]workgroupm[] before a Windows NT PDC is able to do so then cross subnet browsing will behave strangely and may fail.
If m[blue]domain logons = yesm[], then the default behavior is to enable the m[blue]domain masterm[] parameter. If m[blue]domain logonsm[] is not enabled (the default setting), then neither will m[blue]domain masterm[] be enabled by default.
When m[blue]domain logons = Yesm[] the default setting for this parameter is Yes, with the result that Samba will be a PDC. If m[blue]domain master = Nom[], Samba will function as a BDC. In general, this parameter should be set to 'No' only on a BDC.
Default: domain master = auto
dont descend (S)
Note that Samba can be very fussy about the exact format of the "dont descend" entries. For example you may need ./proc instead of just /proc. Experimentation is the best policy :-)
Default: dont descend =
Example: dont descend = /proc,/dev
dos charset (G)
The default depends on which charsets you have installed. Samba tries to use charset 850 but falls back to ASCII in case it is not available. Run testparm(1) to check the default on your system.
No default
dos filemode (S)
Default: dos filemode = no
dos filetime resolution (S)
This option is mainly used as a compatibility option for Visual C++ when used against Samba shares. If oplocks are enabled on a share, Visual C++ uses two different time reading calls to check if a file has changed since it was last read. One of these calls uses a one-second granularity, the other uses a two second granularity. As the two second call rounds any odd second down, then if the file has a timestamp of an odd number of seconds then the two timestamps will not match and Visual C++ will keep reporting the file has changed. Setting this option causes the two timestamps to match, and Visual C++ is happy.
Default: dos filetime resolution = no
dos filetimes (S)
Default: dos filetimes = yes
dsdb event notification (G)
This should be considered a developer option (it assists in the Samba testsuite) rather than a facility for external auditing, as message delivery is not guaranteed (a feature that the testsuite works around).
The Samba database events are also logged via the normal logging methods when the m[blue]log levelm[] is set appropriately.
Default: dsdb event notification = no
dsdb group change notification (G)
This should be considered a developer option (it assists in the Samba testsuite) rather than a facility for external auditing, as message delivery is not guaranteed (a feature that the testsuite works around).
The group events are also logged via the normal logging methods when the m[blue]log levelm[] is set appropriately.
Default: dsdb group change notification = no
dsdb password event notification (G)
This should be considered a developer option (it assists in the Samba testsuite) rather than a facility for external auditing, as message delivery is not guaranteed (a feature that the testsuite works around).
The password events are also logged via the normal logging methods when the m[blue]log levelm[] is set appropriately.
Default: dsdb password event notification = no
durable handles (S)
Note that durable handles are only enabled if m[blue]kernel oplocks = nom[], m[blue]kernel share modes = nom[], and m[blue]posix locking = nom[], i.e. if the share is configured for CIFS/SMB2 only access, not supporting interoperability features with local UNIX processes or NFS operations.
Also note that, for the time being, durability is not granted for a handle that has the delete on close flag set.
Default: durable handles = yes
ea support (S)
Default: ea support = yes
elasticsearch:address (S)
Default: elasticsearch:address = localhost
Example: elasticsearch:address = needle.haystack.samba.org
elasticsearch:index (S)
Default: elasticsearch:index = _all
Example: elasticsearch:index = spotlight
elasticsearch:mappings (G)
Default: elasticsearch:mappings = /usr/share/samba/elasticsearch_mappings.json
Example: elasticsearch:mappings = /usr/share/foo/mymappings.json
elasticsearch:max results (S)
Default: elasticsearch:max results = 100
Example: elasticsearch:max results = 10
elasticsearch:port (S)
Default: elasticsearch:port = 9200
Example: elasticsearch:port = 9201
elasticsearch:use tls (S)
Default: elasticsearch:use tls = no
Example: elasticsearch:use tls = yes
enable asu support (G)
Default: enable asu support = no
enable core files (G)
Default: enable core files = yes
Example: enable core files = no
enable privileges (G)
An example of how privileges can be used is to assign the right to join clients to a Samba controlled domain without providing root access to the server via smbd.
Please read the extended description provided in the Samba HOWTO documentation.
Default: enable privileges = yes
enable spoolss (G)
Default: enable spoolss = yes
encrypt passwords (G)
That is, in the future, the current default of encrypt passwords = yes will be the enforced behaviour.
This boolean controls whether encrypted passwords will be negotiated with the client. Note that Windows NT 4.0 SP3 and above and also Windows 98 will by default expect encrypted passwords unless a registry entry is changed. To use encrypted passwords in Samba see the chapter "User Database" in the Samba HOWTO Collection.
MS Windows clients that expect Microsoft encrypted passwords and that do not have plain text password support enabled will be able to connect only to a Samba server that has encrypted password support enabled and for which the user accounts have a valid encrypted password. Refer to the smbpasswd command man page for information regarding the creation of encrypted passwords for user accounts.
The use of plain text passwords is NOT advised as support for this feature is no longer maintained in Microsoft Windows products. If you want to use plain text passwords you must set this parameter to no.
In order for encrypted passwords to work correctly smbd(8) must either have access to a local smbpasswd(5) file (see the smbpasswd(8) program for information on how to set up and maintain this file), or set the m[blue]security = [domain|ads]m[] parameter which causes smbd to authenticate against another server.
Default: encrypt passwords = yes
enhanced browsing (G)
The first enhancement to browse propagation consists of a regular wildcard query to a Samba WINS server for all Domain Master Browsers, followed by a browse synchronization with each of the returned DMBs. The second enhancement consists of a regular randomised browse synchronization with all currently known DMBs.
You may wish to disable this option if you have a problem with empty workgroups not disappearing from browse lists. Due to the restrictions of the browse protocols, these enhancements can cause a empty workgroup to stay around forever which can be annoying.
In general you should leave this option enabled as it makes cross-subnet browse propagation much more reliable.
Default: enhanced browsing = yes
enumports command (G)
Default: enumports command =
Example: enumports command = /usr/bin/listports
eventlog list (G)
The administrator must use an external process to parse the normal Unix logs such as /var/log/messages and write then entries to the eventlog tdb files. Refer to the eventlogadm(8) utility for how to write eventlog entries.
Default: eventlog list =
Example: eventlog list = Security Application Syslog Apache
fake directory create times (S)
This option is mainly used as a compatibility option for Visual C++ when used against Samba shares. Visual C++ generated makefiles have the object directory as a dependency for each object file, and a make rule to create the directory. Also, when NMAKE compares timestamps it uses the creation time when examining a directory. Thus the object directory will be created if it does not exist, but once it does exist it will always have an earlier timestamp than the object files it contains.
However, Unix time semantics mean that the create time reported by Samba will be updated whenever a file is created or deleted in the directory. NMAKE finds all object files in the object directory. The timestamp of the last one built is then compared to the timestamp of the object directory. If the directory's timestamp if newer, then all object files will be rebuilt. Enabling this option ensures directories always predate their contents and an NMAKE build will proceed as expected.
Default: fake directory create times = no
fake oplocks (S)
When you set fake oplocks = yes, smbd(8) will always grant oplock requests no matter how many clients are using the file.
It is generally much better to use the real m[blue]oplocksm[] support rather than this parameter.
If you enable this option on all read-only shares or shares that you know will only be accessed from one client at a time such as physically read-only media like CDROMs, you will see a big performance improvement on many operations. If you enable this option on shares where multiple clients may be accessing the files read-write at the same time you can get data corruption. Use this option carefully!
Default: fake oplocks = no
follow symlinks (S)
This option is enabled (i.e. smbd will follow symbolic links) by default.
Default: follow symlinks = yes
smbd force process locks (S)
This option should not be changed from the default unless you know what you're doing.
Default: smbd force process locks = no
force create mode (S)
The example below would force all newly created files to have read and execute permissions set for 'group' and 'other' as well as the read/write/execute bits set for the 'user'.
Default: force create mode = 0000
Example: force create mode = 0755
force directory mode (S)
The example below would force all created directories to have read and execute permissions set for 'group' and 'other' as well as the read/write/execute bits set for the 'user'.
Default: force directory mode = 0000
Example: force directory mode = 0755
force directory security mode (S)
No default
group
force group (S)
In Samba 2.0.5 and above this parameter has extended functionality in the following way. If the group name listed here has a '+' character prepended to it then the current user accessing the share only has the primary group default assigned to this group if they are already assigned as a member of that group. This allows an administrator to decide that only users who are already in a particular group will create files with group ownership set to that group. This gives a finer granularity of ownership assignment. For example, the setting force group = +sys means that only users who are already in group sys will have their default primary group assigned to sys when accessing this Samba share. All other users will retain their ordinary primary group.
If the m[blue]force userm[] parameter is also set the group specified in force group will override the primary group set in force user.
Default: force group =
Example: force group = agroup
force printername (S)
When assigning a new driver to a printer on a remote Windows compatible print server such as Samba, the Windows client will rename the printer to match the driver name just uploaded. This can result in confusion for users when multiple printers are bound to the same driver. To prevent Samba from allowing the printer's printername to differ from the sharename defined in smb.conf, set force printername = yes.
Be aware that enabling this parameter may affect migrating printers from a Windows server to Samba since Windows has no way to force the sharename and printername to match.
It is recommended that this parameter's value not be changed once the printer is in use by clients as this could cause a user not be able to delete printer connections from their local Printers folder.
Default: force printername = no
force security mode (S)
No default
force unknown acl user (S)
This is designed to allow Windows NT clients to copy files and folders containing ACLs that were created locally on the client machine and contain users local to that machine only (no domain users) to be copied to a Samba server (usually with XCOPY /O) and have the unknown userid and groupid of the file owner map to the current connected user. This can only be fixed correctly when winbindd allows arbitrary mapping from any Windows NT SID to a UNIX uid or gid.
Try using this parameter when XCOPY /O gives an ACCESS_DENIED error.
Default: force unknown acl user = no
force user (S)
This user name only gets used once a connection is established. Thus clients still need to connect as a valid user and supply a valid password. Once connected, all file operations will be performed as the "forced user", no matter what username the client connected as. This can be very useful.
In Samba 2.0.5 and above this parameter also causes the primary group of the forced user to be used as the primary group for all file activity. Prior to 2.0.5 the primary group was left as the primary group of the connecting user (this was a bug).
Default: force user =
Example: force user = auser
fss: prune stale (G)
Default: fss: prune stale = no
Example: fss: prune stale = yes
fss: sequence timeout (G)
Default: fss: sequence timeout = 180 or 1800, depending on operation
Example: fss: sequence timeout = 0
fstype (S)
Default: fstype = NTFS
Example: fstype = Samba
get quota command (G)
This option is only available Samba was compiled with quotas support.
This parameter should specify the path to a script that queries the quota information for the specified user/group for the partition that the specified directory is on.
Such a script is being given 3 arguments:
The type of query can be one of:
Example: get quota command = /usr/local/sbin/query_quota
getwd cache (G)
Default: getwd cache = yes
gpo update command (G)
Default: gpo update command = /builddir/build/BUILD/samba-4.14.2/source4/scripting/bin/samba-gpupdate
Example: gpo update command = /usr/local/sbin/gpoupdate
guest account (G)
On some systems the default guest account "nobody" may not be able to print. Use another account in this case. You should test this by trying to log in as your guest user (perhaps by using the su - command) and trying to print using the system print command such as lpr(1) or lp(1).
This parameter does not accept % macros, because many parts of the system require this value to be constant for correct operation.
Default: guest account = nobody # default can be changed at compile-time
Example: guest account = ftp
public
guest ok (S)
This parameter nullifies the benefits of setting m[blue]restrict anonymous = 2m[]
See the section below on m[blue]securitym[] for more information about this option.
Default: guest ok = no
only guest
guest only (S)
See the section below on m[blue]securitym[] for more information about this option.
Default: guest only = no
hide dot files (S)
Default: hide dot files = yes
hide files (S)
Each entry in the list must be separated by a '/', which allows spaces to be included in the entry. '*' and '?' can be used to specify multiple files or directories as in DOS wildcards.
Each entry must be a Unix path, not a DOS path and must not include the Unix directory separator '/'.
Note that the case sensitivity option is applicable in hiding files.
Setting this parameter will affect the performance of Samba, as it will be forced to check all files and directories for a match as they are scanned.
The example shown above is based on files that the Macintosh SMB client (DAVE) available from Thursby creates for internal use, and also still hides all files beginning with a dot.
An example of us of this parameter is:
hide files = /.*/DesktopFolderDB/TrashFor%m/resource.frk/
Default: hide files = # no file are hidden
hide new files timeout (S)
It can be used for ingest/process queue style workloads. A processing application should only see files that are definitely finished. As many applications do not have proper external workflow control, this can be a way to make sure processing does not interfere with file ingest.
Default: hide new files timeout = 0
hide special files (S)
Default: hide special files = no
hide unreadable (S)
Please note that enabling this can slow down listing large directories significantly. Samba has to evaluate the ACLs of all directory members, which can be a lot of effort.
Default: hide unreadable = no
hide unwriteable files (S)
Please note that enabling this can slow down listing large directories significantly. Samba has to evaluate the ACLs of all directory members, which can be a lot of effort.
Default: hide unwriteable files = no
homedir map (G)
username server:/some/file/system
and the program will extract the servername from before the first ':'. There should probably be a better parsing system that copes with different map formats and also Amd (another automounter) maps.
Example: homedir map = amd.homedir
honor change notify privilege (S)
If "honor change notify privilege" is enabled, a user will only receive notify results, if he has change notify privilege or sufficient file system permissions. If a user has the change notify privilege, he will receive all requested notify results, even if the user does not have the permissions on the file system.
Default: honor change notify privilege = no
host msdfs (G)
See also the m[blue]msdfs rootm[] share level parameter. For more information on setting up a Dfs tree on Samba, refer to the MSFDS chapter in the book Samba3-HOWTO.
Default: host msdfs = yes
hostname lookups (G)
Default: hostname lookups = no
Example: hostname lookups = yes
allow hosts
hosts allow (S)
This parameter is a comma, space, or tab delimited set of hosts which are permitted to access a service.
If specified in the [global] section then it will apply to all services, regardless of whether the individual service has a different setting.
You can specify the hosts by name or IP number. For example, you could restrict access to only the hosts on a Class C subnet with something like allow hosts = 150.203.5.. The full syntax of the list is described in the man page hosts_access(5). Note that this man page may not be present on your system, so a brief description will be given here also.
Note that the localhost address 127.0.0.1 will always be allowed access unless specifically denied by a m[blue]hosts denym[] option.
You can also specify hosts by network/netmask pairs and by netgroup names if your system supports netgroups. The EXCEPT keyword can also be used to limit a wildcard list. The following examples may provide some help:
Example 1: allow all IPs in 150.203.*.*; except one
hosts allow = 150.203. EXCEPT 150.203.6.66
Example 2: allow hosts that match the given network/netmask
hosts allow = 150.203.15.0/255.255.255.0
Example 3: allow a couple of hosts
hosts allow = lapland, arvidsjaur
Example 4: allow only hosts in NIS netgroup "foonet", but deny access from one particular host
hosts allow = @foonet
hosts deny = pirate
Default: hosts allow = # none (i.e., all hosts permitted access)
Example: hosts allow = 150.203.5. myhost.mynet.edu.au
deny hosts
hosts deny (S)
In the event that it is necessary to deny all by default, use the keyword ALL (or the netmask 0.0.0.0/0) and then explicitly specify to the m[blue]hosts allow = hosts allowm[] parameter those hosts that should be permitted access.
Default: hosts deny = # none (i.e., no hosts specifically excluded)
Example: hosts deny = 150.203.4. badhost.mynet.edu.au
idmap backend (G)
This option specifies the default backend that is used when no special configuration set, but it is now deprecated in favour of the new spelling m[blue]idmap config * : backendm[].
Default: idmap backend = tdb
idmap cache time (G)
Default: idmap cache time = 604800
idmap config DOMAIN : OPTION (G)
The idmap configuration is hence divided into groups, one group for each domain to be configured, and one group with the asterisk instead of a proper domain name, which specifies the default configuration that is used to catch all domains that do not have an explicit idmap configuration of their own.
There are three general options available:
backend = backend_name
The first three of these create mappings of their own using internal unixid counters and store the mappings in a database. These are suitable for use in the default idmap configuration. The rid and hash backends use a pure algorithmic calculation to determine the unixid for a SID. The autorid module is a mixture of the tdb and rid backend. It creates ranges for each domain encountered and then uses the rid algorithm for each of these automatically configured domains individually. The ad backend uses unix ids stored in Active Directory via the standard schema extensions. The nss backend reverses the standard winbindd setup and gets the unix ids via names from nsswitch which can be useful in an ldap setup.
range = low - high
winbind uses this parameter to find the backend that is authoritative for a unix ID to SID mapping, so it must be set for each individually configured domain and for the default configuration. The configured ranges must be mutually disjoint.
read only = yes|no
The following example illustrates how to configure the idmap_ad(8) backend for the CORP domain and the idmap_tdb(8) backend for all other domains. This configuration assumes that the admin of CORP assigns unix ids below 1000000 via the SFU extensions, and winbind is supposed to use the next million entries for its own mappings from trusted domains and for local groups for example.
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999
idmap config CORP : backend = ad
idmap config CORP : range = 1000-999999
No default
winbind gid
idmap gid (G)
See the m[blue]idmap configm[] option.
Default: idmap gid =
Example: idmap gid = 10000-20000
idmap negative cache time (G)
Default: idmap negative cache time = 120
winbind uid
idmap uid (G)
See the m[blue]idmap configm[] option.
Default: idmap uid =
Example: idmap uid = 10000-20000
include (S)
It takes the standard substitutions, except %u, %P and %S.
The parameter include = registry has a special meaning: It does not include a file named registry from the current working directory, but instead reads the global configuration options from the registry. See the section on registry-based configuration for details. Note that this option automatically activates registry shares.
Default: include =
Example: include = /usr/local/samba/lib/admin_smb.conf
include system krb5 conf (G)
Default: include system krb5 conf = yes
inherit acls (S)
Default: inherit acls = no
inherit owner (S)
Valid options are:
The unix only option effectively breaks the tie between the Windows owner of a file and the UNIX owner. As a logical consequence, in this mode, setting the the Windows owner of a file does not modify the UNIX owner. Using this mode should typically be combined with a backing store that can emulate the full NT ACL model without affecting the POSIX permissions, such as the acl_xattr VFS module, coupled with m[blue]acl_xattr:ignore system acls = yesm[]. This can be used to emulate folder quotas, when files are exposed only via SMB (without UNIX extensions). The UNIX owner of a directory is locally set and inherited by all subdirectories and files, and they all consume the same quota.
Default: inherit owner = no
inherit permissions (S)
New directories inherit the mode of the parent directory, including bits such as setgid.
New files inherit their read/write bits from the parent directory. Their execute bits continue to be determined by m[blue]map archivem[], m[blue]map hiddenm[] and m[blue]map systemm[] as usual.
Note that the setuid bit is never set via inheritance (the code explicitly prohibits this).
This can be particularly useful on large systems with many users, perhaps several thousand, to allow a single [homes] share to be used flexibly by each user.
Default: inherit permissions = no
init logon delay (G)
Default: init logon delay = 100
init logon delayed hosts (G)
The length of the delay can be specified with the m[blue]init logon delaym[] parameter.
Default: init logon delayed hosts =
Example: init logon delayed hosts = 150.203.5. myhost.mynet.de
interfaces (G)
The option takes a list of interface strings. Each string can be in any of the following forms:
The "IP" parameters above can either be a full dotted decimal IP address or a hostname which will be looked up via the OS's normal hostname resolution mechanisms.
By default Samba enables all active interfaces that are broadcast capable except the loopback adaptor (IP address 127.0.0.1).
In order to support SMB3 multi-channel configurations, smbd understands some extra parameters which can be appended after the actual interface with this extended syntax (note that the quoting is important in order to handle the ; and , characters):
"interface[;key1=value1[,key2=value2[...]]]"
Known keys are speed, capability, and if_index. Speed is specified in bits per second. Known capabilities are RSS and RDMA. The if_index should be used with care: the values must not coincide with indexes used by the kernel. Note that these options are mainly intended for testing and development rather than for production use. At least on Linux systems, these values should be auto-detected, but the settings can serve as last a resort when autodetection is not working or is not available. The specified values overwrite the auto-detected values.
The first two example below configures three network interfaces corresponding to the eth0 device and IP addresses 192.168.2.10 and 192.168.3.10. The netmasks of the latter two interfaces would be set to 255.255.255.0.
The other examples show how per interface extra parameters can be specified. Notice the possible usage of "," and ";", which makes the double quoting necessary.
Default: interfaces =
Example: interfaces = eth0 192.168.2.10/24 192.168.3.10/255.255.255.0
Example: interfaces = eth0, 192.168.2.10/24; 192.168.3.10/255.255.255.0
Example: interfaces = "eth0;if_index=65,speed=1000000000,capability=RSS"
Example: interfaces = "lo;speed=1000000000" "eth0;capability=RSS"
Example: interfaces = "lo;speed=1000000000" , "eth0;capability=RSS"
Example: interfaces = "eth0;capability=RSS" , "rdma1;capability=RDMA" ; "rdma2;capability=RSS,capability=RDMA"
invalid users (S)
A name starting with a '@' is interpreted as an NIS netgroup first (if your system supports NIS), and then as a UNIX group if the name was not found in the NIS netgroup database.
A name starting with '+' is interpreted only by looking in the UNIX group database via the NSS getgrnam() interface. A name starting with '&' is interpreted only by looking in the NIS netgroup database (this requires NIS to be working on your system). The characters '+' and '&' may be used at the start of the name in either order so the value +&group means check the UNIX group database, followed by the NIS netgroup database, and the value &+group means check the NIS netgroup database, followed by the UNIX group database (the same as the '@' prefix).
The current servicename is substituted for %S. This is useful in the [homes] section.
Default: invalid users = # no invalid users
Example: invalid users = root fred admin @wheel
iprint server (G)
If set, this option overrides the ServerName option in the CUPS client.conf. This is necessary if you have virtual samba servers that connect to different CUPS daemons.
Default: iprint server = ""
Example: iprint server = MYCUPSSERVER
keepalive (G)
Keepalives should, in general, not be needed if the socket has the SO_KEEPALIVE attribute set on it by default. (see m[blue]socket optionsm[]). Basically you should only use this option if you strike difficulties.
Please note this option only applies to SMB1 client connections, and has no effect on SMB2 clients.
Default: keepalive = 300
Example: keepalive = 600
kerberos encryption types (G)
Samba uses a Kerberos library (MIT or Heimdal) to obtain Kerberos tickets. This library is normally configured outside of Samba, using the krb5.conf file. This file may also include directives to configure the encryption types to be used. However, Samba implements Active Directory protocols and algorithms to locate a domain controller. In order to force the Kerberos library into using the correct domain controller, some Samba processes, such as winbindd(8) and net(8), build a private krb5.conf file for use by the Kerberos library while being invoked from Samba. This private file controls all aspects of the Kerberos library operation, and this parameter controls how the encryption types are configured within this generated file, and therefore also controls the encryption types negotiable by Samba.
When set to all, all active directory encryption types are allowed.
When set to strong, only AES-based encryption types are offered. This can be used in hardened environments to prevent downgrade attacks.
When set to legacy, only RC4-HMAC-MD5 is allowed. Avoiding AES this way has one a very specific use. Normally, the encryption type is negotiated between the peers. However, there is one scenario in which a Windows read-only domain controller (RODC) advertises AES encryption, but then proxies the request to a writeable DC which may not support AES encryption, leading to failure of the handshake. Setting this parameter to legacy would cause samba not to negotiate AES encryption. It is assumed of course that the weaker legacy encryption types are acceptable for the setup.
Default: kerberos encryption types = all
kerberos method (G)
Valid options are:
When the kerberos method is in "dedicated keytab" mode, m[blue]dedicated keytab filem[] must be set to specify the location of the keytab file.
Default: kerberos method = default
kernel change notify (G)
This parameter is only used when your kernel supports change notification to user programs using the inotify interface.
Default: kernel change notify = yes
kernel oplocks (S)
Kernel oplocks support allows Samba oplocks to be broken whenever a local UNIX process or NFS operation accesses a file that smbd(8) has oplocked. This allows complete data consistency between SMB/CIFS, NFS and local file access (and is a very cool feature :-).
If you do not need this interaction, you should disable the parameter on Linux to get Level II oplocks and the associated performance benefit.
This parameter defaults to no and is translated to a no-op on systems that do not have the necessary kernel support.
Default: kernel oplocks = no
kernel share modes (S)
Kernel share modes provide a minimal level of interoperability with local UNIX processes and NFS operations by preventing access with flocks corresponding to the SMB share modes. Generally, it is very desirable to leave this enabled.
Note that in order to use SMB2 durable file handles on a share, you have to turn kernel share modes off.
This parameter defaults to yes and is translated to a no-op on systems that do not have the necessary kernel flock support.
Default: kernel share modes = yes
kpasswd port (G)
Default: kpasswd port = 464
krb5 port (G)
Default: krb5 port = 88
lanman auth (G)
That is, in the future, the current default of lanman auth = no will be the enforced behaviour.
This parameter determines whether or not smbd(8) will attempt to authenticate users or permit password changes using the LANMAN password hash. If disabled, only clients which support NT password hashes (e.g. Windows NT/2000 clients, smbclient, but not Windows 95/98 or the MS DOS network client) will be able to connect to the Samba host.
The LANMAN encrypted response is easily broken, due to its case-insensitive nature, and the choice of algorithm. Servers without Windows 95/98/ME or MS DOS clients are advised to disable this option.
When this parameter is set to no this will also result in sambaLMPassword in Samba's passdb being blanked after the next password change. As a result of that lanman clients won't be able to authenticate, even if lanman auth is re-enabled later on.
Unlike the encrypt passwords option, this parameter cannot alter client behaviour, and the LANMAN response will still be sent over the network. See the client lanman auth to disable this for Samba's clients (such as smbclient)
This parameter is overridden by ntlm auth, so unless that it is also set to ntlmv1-permitted or yes, then only NTLMv2 logins will be permitted and no LM hash will be stored. All modern clients support NTLMv2, and but some older clients require special configuration to use it.
Default: lanman auth = no
large readwrite (G)
Default: large readwrite = yes
ldap admin dn (G)
The m[blue]ldap admin dnm[] requires a fully specified DN. The m[blue]ldap suffixm[] is not appended to the m[blue]ldap admin dnm[].
No default
ldap connection timeout (G)
This parameter is different from m[blue]ldap timeoutm[] which affects operations on LDAP servers using an existing connection and not establishing an initial connection.
Default: ldap connection timeout = 2
ldap debug level (G)
The debug output from the LDAP libraries appears with the prefix [LDAP] in Samba's logging output. The level at which LDAP logging is printed is controlled by the parameter ldap debug threshold.
Default: ldap debug level = 0
Example: ldap debug level = 1
ldap debug threshold (G)
Default: ldap debug threshold = 10
Example: ldap debug threshold = 5
ldap delete dn (G)
Default: ldap delete dn = no
ldap deref (G)
Default: ldap deref = auto
Example: ldap deref = searching
ldap follow referral (G)
Default: ldap follow referral = auto
Example: ldap follow referral = off
ldap group suffix (G)
Default: ldap group suffix =
Example: ldap group suffix = ou=Groups
ldap idmap suffix (G)
Default: ldap idmap suffix =
Example: ldap idmap suffix = ou=Idmap
ldap machine suffix (G)
Default: ldap machine suffix =
Example: ldap machine suffix = ou=Computers
ldap max anonymous request size (G)
If the request size exceeds this limit the request will be rejected.
Default: ldap max anonymous request size = 256000
Example: ldap max anonymous request size = 500000
ldap max authenticated request size (G)
If the request size exceeds this limit the request will be rejected.
Default: ldap max authenticated request size = 16777216
Example: ldap max authenticated request size = 4194304
ldap max search request size (G)
If the request size exceeds this limit the request will be rejected.
Default: ldap max search request size = 256000
Example: ldap max search request size = 4194304
ldap page size (G)
If the LDAP server supports paged results, clients can request subsets of search results (pages) instead of the entire list. This parameter specifies the size of these pages.
Default: ldap page size = 1000
Example: ldap page size = 512
ldap password sync
ldap passwd sync (G)
The m[blue]ldap passwd syncm[] can be set to one of three values:
ldap replication sleep (G)
This option simply causes Samba to wait a short time, to allow the LDAP server to catch up. If you have a particularly high-latency network, you may wish to time the LDAP replication with a network sniffer, and increase this value accordingly. Be aware that no checking is performed that the data has actually replicated.
The value is specified in milliseconds, the maximum value is 5000 (5 seconds).
Default: ldap replication sleep = 1000
ldapsam:editposix (G)
To use this option, a basic ldap tree must be provided and the ldap suffix parameters must be properly configured. On virgin servers the default users and groups (Administrator, Guest, Domain Users, Domain Admins, Domain Guests) can be precreated with the command net sam provision. To run this command the ldap server must be running, Winbindd must be running and the smb.conf ldap options must be properly configured. The typical ldap setup used with the m[blue]ldapsam:trusted = yesm[] option is usually sufficient to use m[blue]ldapsam:editposix = yesm[] as well.
An example configuration can be the following:
encrypt passwords = true
passdb backend = ldapsam
ldapsam:trusted=yes
ldapsam:editposix=yes
ldap admin dn = cn=admin,dc=samba,dc=org
ldap delete dn = yes
ldap group suffix = ou=groups
ldap idmap suffix = ou=idmap
ldap machine suffix = ou=computers
ldap user suffix = ou=users
ldap suffix = dc=samba,dc=org
idmap backend = ldap:"ldap://localhost"
idmap uid = 5000-50000
idmap gid = 5000-50000
This configuration assumes a directory layout like described in the following ldif:
dn: dc=samba,dc=org
objectClass: top
objectClass: dcObject
objectClass: organization
o: samba.org
dc: samba
dn: cn=admin,dc=samba,dc=org
objectClass: simpleSecurityObject
objectClass: organizationalRole
cn: admin
description: LDAP administrator
userPassword: secret
dn: ou=users,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: users
dn: ou=groups,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: groups
dn: ou=idmap,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: idmap
dn: ou=computers,dc=samba,dc=org
objectClass: top
objectClass: organizationalUnit
ou: computers
Default: ldapsam:editposix = no
ldapsam:trusted (G)
To make Samba scale well in large environments, the m[blue]ldapsam:trusted = yesm[] option assumes that the complete user and group database that is relevant to Samba is stored in LDAP with the standard posixAccount/posixGroup attributes. It further assumes that the Samba auxiliary object classes are stored together with the POSIX data in the same LDAP object. If these assumptions are met, m[blue]ldapsam:trusted = yesm[] can be activated and Samba can bypass the NSS system to query user group memberships. Optimized LDAP queries can greatly speed up domain logon and administration tasks. Depending on the size of the LDAP database a factor of 100 or more for common queries is easily achieved.
Default: ldapsam:trusted = no
ldap server require strong auth (G)
A value of no allows simple and sasl binds over all transports.
A value of allow_sasl_over_tls allows simple and sasl binds (without sign or seal) over TLS encrypted connections. Unencrypted connections only allow sasl binds with sign or seal.
A value of yes allows only simple binds over TLS encrypted connections. Unencrypted connections only allow sasl binds with sign or seal.
Default: ldap server require strong auth = yes
ldap ssl (G)
LDAP connections should be secured where possible. This may be done setting either this parameter to start tls or by specifying ldaps:// in the URL argument of m[blue]passdb backendm[].
The m[blue]ldap sslm[] can be set to one of two values:
Default: ldap ssl = start tls
ldap suffix (G)
The ldap suffix will be appended to the values specified for the m[blue]ldap user suffixm[], m[blue]ldap group suffixm[], m[blue]ldap machine suffixm[], and the m[blue]ldap idmap suffixm[]. Each of these should be given only a DN relative to the m[blue]ldap suffixm[].
Default: ldap suffix =
Example: ldap suffix = dc=samba,dc=org
ldap timeout (G)
Default: ldap timeout = 15
ldap user suffix (G)
Default: ldap user suffix =
Example: ldap user suffix = ou=people
level2 oplocks (S)
Level2, or read-only oplocks allow Windows NT clients that have an oplock on a file to downgrade from a read-write oplock to a read-only oplock once a second client opens the file (instead of releasing all oplocks on a second open, as in traditional, exclusive oplocks). This allows all openers of the file that support level2 oplocks to cache the file for read-ahead only (ie. they may not cache writes or lock requests) and increases performance for many accesses of files that are not commonly written (such as application .EXE files).
Once one of the clients which have a read-only oplock writes to the file all clients are notified (no reply is needed or waited for) and told to break their oplocks to "none" and delete any read-ahead caches.
It is recommended that this parameter be turned on to speed access to shared executables.
For more discussions on level2 oplocks see the CIFS spec.
Currently, if m[blue]kernel oplocksm[] are supported then level2 oplocks are not granted (even if this parameter is set to yes). Note also, the m[blue]oplocksm[] parameter must be set to yes on this share in order for this parameter to have any effect.
Default: level2 oplocks = yes
lm announce (G)
Default: lm announce = auto
Example: lm announce = yes
lm interval (G)
Default: lm interval = 60
Example: lm interval = 120
load printers (G)
Default: load printers = yes
local master (G)
Setting this value to no will cause nmbd never to become a local master browser.
Default: local master = yes
lock dir
lock directory (G)
Note: This option can not be set inside registry configurations.
The files placed in this directory are not required across service restarts and can be safely placed on volatile storage (e.g. tmpfs in Linux)
Default: lock directory = /var/lib/samba/lock
Example: lock directory = /var/run/samba/locks
locking (S)
If locking = no, all lock and unlock requests will appear to succeed and all lock queries will report that the file in question is available for locking.
If locking = yes, real locking will be performed by the server.
This option may be useful for read-only filesystems which may not need locking (such as CDROM drives), although setting this parameter of no is not really recommended even in this case.
Be careful about disabling locking either globally or in a specific service, as lack of locking may result in data corruption. You should never need to set this parameter.
Default: locking = yes
lock spin time (G)
Default: lock spin time = 200
log file (G)
This option takes the standard substitutions, allowing you to have separate log files for each user or machine.
No default
Example: log file = /usr/local/samba/var/log.%m
logging (G)
The 'option' parameter can be used to pass backend-specific options.
The log level for a backend is optional, if it is not set for a backend, all messages are sent to this backend. The parameter m[blue]log levelm[] determines overall log levels, while the log levels specified here define what is sent to the individual backends.
When m[blue]loggingm[] is set, it overrides the m[blue]syslogm[] and m[blue]syslog onlym[] parameters.
Some backends are only available when Samba has been compiled with the additional libraries. The overall list of logging backends:
Default: logging =
Example: logging = syslog@1 file
debuglevel
log level (G)
This parameter has been extended since the 2.2.x series, now it allows one to specify the debug level for multiple debug classes and distinct logfiles for debug classes. This is to give greater flexibility in the configuration of the system. The following debug classes are currently implemented:
Authentication and authorization audit information is logged under the auth_audit, and if Samba was not compiled with --without-json, a JSON representation is logged under auth_json_audit.
Support is comprehensive for all authentication and authorisation of user accounts in the Samba Active Directory Domain Controller, as well as the implicit authentication in password changes. In the file server, NTLM authentication, SMB and RPC authorization is covered.
Log levels for auth_audit and auth_audit_json are:
Password changes and Password resets are logged under dsdb_password_audit and a JSON representation is logged under the dsdb_password_json_audit.
Transaction rollbacks and prepare commit failures are logged under the dsdb_transaction_audit and a JSON representation is logged under the password_json_audit. Logging the transaction details allows the identification of password and sam.ldb operations that have been rolled back.
Default: log level = 0
Example: log level = 3 passdb:5 auth:10 winbind:2
Example: log level = 1 full_audit:1@/var/log/audit.log winbind:2
log nt token command (G)
This is only useful for development purposes.
Default: log nt token command =
logon drive (G)
Note that this option is only useful if Samba is set up as a logon server.
Default: logon drive =
Example: logon drive = h:
logon home (G)
C:\>NET USE H: /HOME
from a command prompt, for example.
This option takes the standard substitutions, allowing you to have separate logon scripts for each user or machine.
This parameter can be used with Win9X workstations to ensure that roaming profiles are stored in a subdirectory of the user's home directory. This is done in the following way:
logon home = \\%N\%U\profile
This tells Samba to return the above string, with substitutions made when a client requests the info, generally in a NetUserGetInfo request. Win9X clients truncate the info to \\server\share when a user does net use /home but use the whole string when dealing with profiles.
Note that in prior versions of Samba, the m[blue]logon pathm[] was returned rather than logon home. This broke net use /home but allowed profiles outside the home directory. The current implementation is correct, and can be used for profiles if you use the above trick.
Disable this feature by setting m[blue]logon home = ""m[] - using the empty string.
This option is only useful if Samba is set up as a logon server.
Default: logon home = \\%N\%U
Example: logon home = \\remote_smb_server\%U
logon path (G)
This option takes the standard substitutions, allowing you to have separate logon scripts for each user or machine. It also specifies the directory from which the "Application Data", desktop, start menu, network neighborhood, programs and other folders, and their contents, are loaded and displayed on your Windows NT client.
The share and the path must be readable by the user for the preferences and directories to be loaded onto the Windows NT client. The share must be writeable when the user logs in for the first time, in order that the Windows NT client can create the NTuser.dat and other directories. Thereafter, the directories and any of the contents can, if required, be made read-only. It is not advisable that the NTuser.dat file be made read-only - rename it to NTuser.man to achieve the desired effect (a MANdatory profile).
Windows clients can sometimes maintain a connection to the [homes] share, even though there is no user logged in. Therefore, it is vital that the logon path does not include a reference to the homes share (i.e. setting this parameter to \\%N\homes\profile_path will cause problems).
This option takes the standard substitutions, allowing you to have separate logon scripts for each user or machine.
Disable the use of roaming profiles by setting the value of this parameter to the empty string. For example, m[blue]logon path = ""m[]. Take note that even if the default setting in the smb.conf file is the empty string, any value specified in the user account settings in the passdb backend will over-ride the effect of setting this parameter to null. Disabling of all roaming profile use requires that the user account settings must also be blank.
An example of use is:
logon path = \\PROFILESERVER\PROFILE\%U
Default: logon path = \\%N\%U\profile
logon script (G)
The script must be a relative path to the [netlogon] service. If the [netlogon] service specifies a m[blue]pathm[] of /usr/local/samba/netlogon, and m[blue]logon script = STARTUP.BATm[], then the file that will be downloaded is:
/usr/local/samba/netlogon/STARTUP.BAT
The contents of the batch file are entirely your choice. A suggested command would be to add NET TIME \\SERVER /SET /YES, to force every machine to synchronize clocks with the same time server. Another use would be to add NET USE U: \\SERVER\UTILS for commonly used utilities, or
NET USE Q: \\SERVER\ISO9001_QA
for example.
Note that it is particularly important not to allow write access to the [netlogon] share, or to grant users write permission on the batch files in a secure environment, as this would allow the batch files to be arbitrarily modified and security to be breached.
This option takes the standard substitutions, allowing you to have separate logon scripts for each user or machine.
This option is only useful if Samba is set up as a logon server in a classic domain controller role. If Samba is set up as an Active Directory domain controller, LDAP attribute scriptPath is used instead. For configurations where m[blue]passdb backend = ldapsamm[] is in use, this option only defines a default value in case LDAP attribute sambaLogonScript is missing.
Default: logon script =
Example: logon script = scripts\%U.bat
log writeable files on exit (G)
Default: log writeable files on exit = no
lppause command (S)
This command should be a program or script which takes a printer name and job number to pause the print job. One way of implementing this is by using job priorities, where jobs having a too low priority won't be sent to the printer.
If a %p is given then the printer name is put in its place. A %j is replaced with the job number (an integer). On HPUX (see printing=hpux ), if the -p%p option is added to the lpq command, the job will show up with the correct status, i.e. if the job priority is lower than the set fence priority it will have the PAUSED status, whereas if the priority is equal or higher it will have the SPOOLED or PRINTING status.
Note that it is good practice to include the absolute path in the lppause command as the PATH may not be available to the server.
Currently no default value is given to this string, unless the value of the m[blue]printingm[] parameter is SYSV, in which case the default is : lp -i %p-%j -H hold or if the value of the printing parameter is SOFTQ, then the default is: qstat -s -j%j -h.
Default: lppause command = # determined by printing parameter
Example: lppause command = /usr/bin/lpalt %p-%j -p0
lpq cache time (G)
The cache files are stored in /tmp/lpq.xxxx where xxxx is a hash of the lpq command in use.
The default is 30 seconds, meaning that the cached results of a previous identical lpq command will be used if the cached data is less than 30 seconds old. A large value may be advisable if your lpq command is very slow.
A value of 0 will disable caching completely.
Default: lpq cache time = 30
Example: lpq cache time = 10
lpq command (S)
This command should be a program or script which takes a printer name as its only parameter and outputs printer status information.
Currently nine styles of printer status information are supported; BSD, AIX, LPRNG, PLP, SYSV, HPUX, QNX, CUPS, and SOFTQ. This covers most UNIX systems. You control which type is expected using the printing = option.
Some clients (notably Windows for Workgroups) may not correctly send the connection number for the printer they are requesting status information about. To get around this, the server reports on the first printer service connected to by the client. This only happens if the connection number sent is invalid.
If a %p is given then the printer name is put in its place. Otherwise it is placed at the end of the command.
Note that it is good practice to include the absolute path in the lpq command as the $PATH may not be available to the server. When compiled with the CUPS libraries, no lpq command is needed because smbd will make a library call to obtain the print queue listing.
Default: lpq command = # determined by printing parameter
Example: lpq command = /usr/bin/lpq -P%p
lpresume command (S)
This command should be a program or script which takes a printer name and job number to resume the print job. See also the m[blue]lppause commandm[] parameter.
If a %p is given then the printer name is put in its place. A %j is replaced with the job number (an integer).
Note that it is good practice to include the absolute path in the lpresume command as the PATH may not be available to the server.
See also the m[blue]printingm[] parameter.
Default: Currently no default value is given to this string, unless the value of the printing parameter is SYSV, in which case the default is:
lp -i %p-%j -H resume
or if the value of the printing parameter is SOFTQ, then the default is:
qstat -s -j%j -r
Default: lpresume command = # determined by printing parameter
Example: lpresume command = /usr/bin/lpalt %p-%j -p2
lprm command (S)
This command should be a program or script which takes a printer name and job number, and deletes the print job.
If a %p is given then the printer name is put in its place. A %j is replaced with the job number (an integer).
Note that it is good practice to include the absolute path in the lprm command as the PATH may not be available to the server.
Examples of use are:
lprm command = /usr/bin/lprm -P%p %j or lprm command = /usr/bin/cancel %p-%j
Default: lprm command = # determined by printing parameter
lsa over netlogon (G)
When enabled, this matches the behaviour of Microsoft's Windows, due to their internal implementation choices.
If it is disabled (the default), the AD DC can offer improved performance, as the netlogon server is decoupled and can run as multiple processes.
Default: lsa over netlogon = no
machine password timeout (G)
See also smbpasswd(8), and the m[blue]security = domainm[] and m[blue]security = adsm[] parameters.
Default: machine password timeout = 604800
magic output (S)
Example: magic output = myfile.txt
magic script (S)
Scripts executed in this way will be deleted upon completion assuming that the user has the appropriate level of privilege and the file permissions allow the deletion.
If the script generates output, output will be sent to the file specified by the m[blue]magic outputm[] parameter (see above).
Note that some shells are unable to interpret scripts containing CR/LF instead of CR as the end-of-line marker. Magic scripts must be executable as is on the host, which for some hosts and some shells will require filtering at the DOS end.
Magic scripts are EXPERIMENTAL and should NOT be relied upon.
Default: magic script =
Example: magic script = user.csh
mangled names (S)
See the section on m[blue]name manglingm[] for details on how to control the mangling process.
Possible option settings are
Note that the character to use may be specified using the m[blue]mangling charm[] option, if you don't like '~'.
This algorithm can cause name collisions only if files in a directory share the same first five alphanumeric characters. The probability of such a clash is 1/1300.
The name mangling (if enabled) allows a file to be copied between UNIX directories from Windows/DOS while retaining the long UNIX filename. UNIX files can be renamed to a new extension from Windows/DOS and will retain the same basename. Mangled names do not change between sessions.
Default: mangled names = illegal
Example: mangled names = no
mangle prefix (G)
mangle prefix is effective only when mangling method is hash2.
Default: mangle prefix = 1
Example: mangle prefix = 4
mangling char (S)
Default: mangling char = ~
Example: mangling char = ^
mangling method (G)
Default: mangling method = hash2
Example: mangling method = hash
map acl inherit (S)
Default: map acl inherit = no
map archive (S)
Note that this parameter will be ignored if the m[blue]store dos attributesm[] parameter is set, as the DOS archive attribute will then be stored inside a UNIX extended attribute.
Note that this requires the m[blue]create maskm[] parameter to be set such that owner execute bit is not masked out (i.e. it must include 100). See the parameter m[blue]create maskm[] for details.
Default: map archive = yes
map hidden (S)
Note that this parameter will be ignored if the m[blue]store dos attributesm[] parameter is set, as the DOS hidden attribute will then be stored inside a UNIX extended attribute.
Note that this requires the m[blue]create maskm[] to be set such that the world execute bit is not masked out (i.e. it must include 001). See the parameter m[blue]create maskm[] for details.
Default: map hidden = no
map readonly (S)
This parameter can take three different values, which tell smbd(8) how to display the read only attribute on files, where either m[blue]store dos attributesm[] is set to No, or no extended attribute is present. If m[blue]store dos attributesm[] is set to yes then this parameter is ignored. This is a new parameter introduced in Samba version 3.0.21.
The three settings are :
The default has changed to no in Samba release 4.9.0 and above to allow better Windows fileserver compatibility in a default install. In addition the default setting of m[blue]store dos attributesm[] has been changed to Yes in Samba release 4.9.0 and above.
Default: map readonly = no
map system (S)
Note that this parameter will be ignored if the m[blue]store dos attributesm[] parameter is set, as the DOS system attribute will then be stored inside a UNIX extended attribute.
Note that this requires the m[blue]create maskm[] to be set such that the group execute bit is not masked out (i.e. it must include 010). See the parameter m[blue]create maskm[] for details.
Default: map system = no
map to guest (G)
The four settings are :
Default: map to guest = Never
Example: map to guest = Bad User
max connections (S)
Record lock files are used to implement this feature. The lock files will be stored in the directory specified by the m[blue]lock directorym[] option.
Default: max connections = 0
Example: max connections = 10
max disk size (G)
Note that this option does not limit the amount of data you can put on the disk. In the above case you could still store much more than 100 MB on the disk, but if a client ever asks for the amount of free disk space or the total disk size then the result will be bounded by the amount specified in max disk size.
This option is primarily useful to work around bugs in some pieces of software that can't handle very large disks, particularly disks over 1GB in size.
A max disk size of 0 means no limit.
Default: max disk size = 0
Example: max disk size = 1000
max log size (G)
A size of 0 means no limit.
Default: max log size = 5000
Example: max log size = 1000
max mux (G)
Default: max mux = 50
max open files (G)
The limit of the number of open files is usually set by the UNIX per-process file descriptor limit rather than this parameter so you should never need to touch this parameter.
Default: max open files = 16384
max print jobs (S)
Default: max print jobs = 1000
Example: max print jobs = 5000
max reported print jobs (S)
Default: max reported print jobs = 0
Example: max reported print jobs = 1000
max smbd processes (G)
For a Samba ADDC running the standard process model this option limits the number of processes forked to handle requests. Currently new processes are only forked for ldap and netlogon requests.
Default: max smbd processes = 0
Example: max smbd processes = 1000
max stat cache size (G)
Default: max stat cache size = 512
Example: max stat cache size = 100
max ttl (G)
Default: max ttl = 259200
max wins ttl (G)
Default: max wins ttl = 518400
max xmit (G)
Default: max xmit = 16644
Example: max xmit = 8192
mdns name (G)
The default is to use the NETBIOS name which is typically the hostname in all capital letters.
A setting of mdns will defer the hostname configuration to the MDNS library that is used.
Default: mdns name = netbios
message command (G)
This would normally be a command that would deliver the message somehow. How this is to be done is up to your imagination.
An example is:
message command = csh -c 'xedit %s;rm %s' &
This delivers the message using xedit, then removes it afterwards. NOTE THAT IT IS VERY IMPORTANT THAT THIS COMMAND RETURN IMMEDIATELY. That's why I have the '&' on the end. If it doesn't return immediately then your PCs may freeze when sending messages (they should recover after 30 seconds, hopefully).
All messages are delivered as the global guest user. The command takes the standard substitutions, although %u won't work (%U may be better in this case).
Apart from the standard substitutions, some additional ones apply. In particular:
Here's a way of sending the messages as mail to root:
message command = /bin/mail -s 'message from %f on %m' root < %s; rm %s
If you don't have a message command then the message won't be delivered and Samba will tell the sender there was an error. Unfortunately WfWg totally ignores the error code and carries on regardless, saying that the message was delivered.
If you want to silently delete it then try:
message command = rm %s
Default: message command =
Example: message command = csh -c 'xedit %s; rm %s' &
min print space (S)
Default: min print space = 0
Example: min print space = 2000
min receivefile size (G)
Note this option will have NO EFFECT if set on a SMB signed connection.
The default is zero, which disables this option.
Default: min receivefile size = 0
min wins ttl (G)
Default: min wins ttl = 21600
mit kdc command (G)
If the KDC is not installed in the default location and wasn't correctly detected during build then you should modify this variable and point it to the correct binary.
Default: mit kdc command = /usr/sbin/krb5kdc
Example: mit kdc command = /opt/mit/sbin/krb5kdc
msdfs proxy (S)
Only Dfs roots can act as proxy shares. Take a look at the m[blue]msdfs rootm[] and m[blue]host msdfsm[] options to find out how to set up a Dfs root share.
No default
Example: msdfs proxy = \otherserver\someshare,\otherserver2\someshare
msdfs root (S)
Default: msdfs root = no
msdfs shuffle referrals (S)
Default: msdfs shuffle referrals = no
multicast dns register (G)
This parameter allows disabling Samba to register itself.
Default: multicast dns register = yes
name cache timeout (G)
Default: name cache timeout = 660
Example: name cache timeout = 0
name resolve order (G)
The options are: "lmhosts", "host", "wins" and "bcast". They cause names to be resolved as follows:
When Samba is functioning in ADS security mode (security = ads) it is advised to use following settings for name resolve order:
name resolve order = wins bcast
DC lookups will still be done via DNS, but fallbacks to netbios names will not inundate your DNS servers with needless queries for DOMAIN<0x1c> lookups.
Default: name resolve order = lmhosts wins host bcast
Example: name resolve order = lmhosts bcast host
socket address
nbt client socket address (G)
Setting this option should never be necessary on usual Samba servers running only one nmbd.
By default Samba will send UDP packets from the OS default address for the destination, and accept replies on 0.0.0.0.
This parameter is deprecated. See m[blue]bind interfaces only = Yesm[] and m[blue]interfacesm[] for the previous behaviour of controlling the normal listening sockets.
Default: nbt client socket address = 0.0.0.0
Example: nbt client socket address = 192.168.2.20
nbtd:wins_prepend1Bto1Cqueries (G)
Default: nbtd:wins_prepend1Bto1Cqueries = yes
nbtd:wins_wins_randomize1Clist (G)
Default: nbtd:wins_wins_randomize1Clist = no
nbtd:wins_randomize1Clist_mask (G)
Default: nbtd:wins_randomize1Clist_mask = 255.255.255.0
nbt port (G)
Default: nbt port = 137
ncalrpc dir (G)
This will allow Samba and other unix processes to interact over DCE/RPC without using TCP/IP. Additionally a sub-directory 'np' has restricted permissions, and allows a trusted communication channel between Samba processes
Default: ncalrpc dir = /run/samba/ncalrpc
Example: ncalrpc dir = /var/run/samba/ncalrpc
netbios aliases (G)
Default: netbios aliases = # empty string (no additional names)
Example: netbios aliases = TEST TEST1 TEST2
netbios name (G)
Note that the maximum length for a NetBIOS name is 15 characters.
There is a bug in Samba that breaks operation of browsing and access to shares if the netbios name is set to the literal name PIPE. To avoid this problem, do not name your Samba server PIPE.
Default: netbios name = # machine DNS name
Example: netbios name = MYNAME
netbios scope (G)
Default: netbios scope =
neutralize nt4 emulation (G)
Typically you should not need set this. It can be useful for upgrades from NT4 to AD domains.
The behavior can be controlled per netbios domain by using 'neutralize nt4 emulation:NETBIOSDOMAIN = yes' as option.
Default: neutralize nt4 emulation = no
NIS homedir (G)
When the Samba logon server is not the actual home directory server, but is mounting the home directories via NFS then two network hops would be required to access the users home directory if the logon server told the client to use itself as the SMB server for home directories (one over SMB and one over NFS). This can be very slow.
This option allows Samba to return the home share as being on a different server to the logon server and as long as a Samba daemon is running on the home directory server, it will be mounted on the Samba client directly from the directory server. When Samba is returning the home share to the client, it will consult the NIS map specified in m[blue]homedir mapm[] and return the server listed there.
Note that for this option to work there must be a working NIS system and the Samba server with this option must also be a logon server.
Default: NIS homedir = no
nmbd bind explicit broadcast (G)
Default: nmbd bind explicit broadcast = yes
nsupdate command (G)
Default: nsupdate command = /usr/bin/nsupdate -g
nt acl support (S)
Default: nt acl support = yes
ntlm auth (G)
If disabled, both NTLM and LanMan authencication against the local passdb is disabled.
Note that these settings apply only to local users, authentication will still be forwarded to and NTLM authentication accepted against any domain we are joined to, and any trusted domain, even if disabled or if NTLMv2-only is enforced here. To control NTLM authentiation for domain users, this must option must be configured on each DC.
By default with ntlm auth set to ntlmv2-only only NTLMv2 logins will be permitted. All modern clients support NTLMv2 by default, but some older clients will require special configuration to use it.
The primary user of NTLMv1 is MSCHAPv2 for VPNs and 802.1x.
The available settings are:
This is the required setting for to enable the lanman auth parameter.
Default: ntlm auth = ntlmv2-only
nt pipe support (G)
Default: nt pipe support = yes
ntp signd socket directory (G)
If a non-default path is specified here, then it is also necessary to make NTP aware of the new path using the ntpsigndsocket directive in ntp.conf.
Default: ntp signd socket directory = /var/lib/samba/ntp_signd
nt status support (G)
You should not need to ever disable this parameter.
Default: nt status support = yes
ntvfs handler (S)
Default: ntvfs handler = unixuid, default
null passwords (G)
See also smbpasswd(5).
Default: null passwords = no
obey pam restrictions (G)
Default: obey pam restrictions = no
old password allowed period (G)
This parameter only applies when m[blue]server rolem[] is set to Active Directory Domain Controller.
Default: old password allowed period = 60
oplock break wait time (G)
oplocks (S)
Oplocks may be selectively turned off on certain files with a share. See the m[blue]veto oplock filesm[] parameter. On some systems oplocks are recognized by the underlying operating system. This allows data synchronization between all access to oplocked files, whether it be via Samba or NFS or a local UNIX process. See the m[blue]kernel oplocksm[] parameter for details.
Default: oplocks = yes
os2 driver map (G)
<nt driver name> = <os2 driver name>.<device name>
For example, a valid entry using the HP LaserJet 5 printer driver would appear as HP LaserJet 5L = LASERJET.HP LaserJet 5L.
The need for the file is due to the printer driver namespace problem described in the chapter on Classical Printing in the Samba3-HOWTO book. For more details on OS/2 clients, please refer to chapter on other clients in the Samba3-HOWTO book.
Default: os2 driver map =
os level (G)
Note: By default, Samba will win a local master browsing election over all Microsoft operating systems except a Windows NT 4.0/2000 Domain Controller. This means that a misconfigured Samba host can effectively isolate a subnet for browsing purposes. This parameter is largely auto-configured in the Samba-3 release series and it is seldom necessary to manually override the default setting. Please refer to the chapter on Network Browsing in the Samba-3 HOWTO document for further information regarding the use of this parameter. Note: The maximum value for this parameter is 255. If you use higher values, counting will start at 0!
Default: os level = 20
Example: os level = 65
pam password change (G)
Default: pam password change = no
panic action (G)
Default: panic action =
Example: panic action = /bin/sleep 90000
passdb backend (G)
The parameter value is divided into two parts, the backend's name, and a 'location' string that has meaning only to that particular backed. These are separated by a : character.
Available backends can include:
LDAP connections should be secured where possible. This may be done using either Start-TLS (see m[blue]ldap sslm[]) or by specifying ldaps:// in the URL argument.
Multiple servers may also be specified in double-quotes. Whether multiple servers are supported or not and the exact syntax depends on the LDAP library you use.
Examples of use are:
passdb backend = tdbsam:/etc/samba/private/passdb.tdb or multi server LDAP URL with OpenLDAP library: passdb backend = ldapsam:"ldap://ldap-1.example.com ldap://ldap-2.example.com" or multi server LDAP URL with Netscape based LDAP library: passdb backend = ldapsam:"ldap://ldap-1.example.com ldap-2.example.com"
Default: passdb backend = tdbsam
passdb expand explicit (G)
Default: passdb expand explicit = no
passwd chat (G)
This chat sequence is often quite site specific, depending on what local methods are used for password control (such as NIS etc).
Note that this parameter only is used if the m[blue]unix password syncm[] parameter is set to yes. This sequence is then called AS ROOT when the SMB password in the smbpasswd file is being changed, without access to the old password cleartext. This means that root must be able to reset the user's password without knowing the text of the previous password. In the presence of NIS/YP, this means that the m[blue]passwd programm[] must be executed on the NIS master.
The string can contain the macro %n which is substituted for the new password. The old password (%o) is only available when m[blue]encrypt passwordsm[] has been disabled. The chat sequence can also contain the standard macros \n, \r, \t and \s to give line-feed, carriage-return, tab and space. The chat sequence string can also contain a '*' which matches any sequence of characters. Double quotes can be used to collect strings with spaces in them into a single string.
If the send string in any part of the chat sequence is a full stop ".", then no string is sent. Similarly, if the expect string is a full stop then no string is expected.
If the m[blue]pam password changem[] parameter is set to yes, the chat pairs may be matched in any order, and success is determined by the PAM result, not any particular output. The \n macro is ignored for PAM conversions.
Default: passwd chat = *new*password* %n\n *new*password* %n\n *changed*
Example: passwd chat = "*Enter NEW password*" %n\n "*Reenter NEW password*" %n\n "*Password changed*"
passwd chat debug (G)
Default: passwd chat debug = no
passwd chat timeout (G)
Default: passwd chat timeout = 2
passwd program (G)
Also note that many passwd programs insist in reasonable passwords, such as a minimum length, or the inclusion of mixed case chars and digits. This can pose a problem as some clients (such as Windows for Workgroups) uppercase the password before sending it.
Note that if the unix password sync parameter is set to yes then this program is called AS ROOT before the SMB password in the smbpasswd file is changed. If this UNIX password change fails, then smbd will fail to change the SMB password also (this is by design).
If the unix password sync parameter is set this parameter MUST USE ABSOLUTE PATHS for ALL programs called, and must be examined for security implications. Note that by default unix password sync is set to no.
Default: passwd program =
Example: passwd program = /bin/passwd %u
password hash gpg key ids (G)
You can specify one or more recipients by key id or user id. Note that 32bit key ids are not allowed, specify at least 64bit.
The value is stored as 'Primary:SambaGPG' in the supplementalCredentials attribute.
As password changes can occur on any domain controller, you should configure this on each of them. Note that this feature is currently available only on Samba domain controllers.
This option is only available if samba was compiled with gpgme support.
You may need to export the GNUPGHOME environment variable before starting samba. It is strongly recommended to only store the public key in this location. The private key is not used for encryption and should be only stored where decryption is required.
Being able to restore the cleartext password helps, when they need to be imported into other authentication systems later (see samba-tool user getpassword) or you want to keep the passwords in sync with another system, e.g. an OpenLDAP server (see samba-tool user syncpasswords).
While this option needs to be configured on all domain controllers, the samba-tool user syncpasswords command should run on a single domain controller only (typically the PDC-emulator).
Default: password hash gpg key ids =
Example: password hash gpg key ids = 4952E40301FAB41A
Example: password hash gpg key ids = selftest@samba.example.com
Example: password hash gpg key ids = selftest@samba.example.com, 4952E40301FAB41A
password hash userPassword schemes (G)
The values are stored as 'Primary:userPassword' in the supplementalCredentials attribute. The value of this option is a hash type.
The currently supported hash types are:
As password changes can occur on any domain controller, you should configure this on each of them. Note that this feature is currently available only on Samba domain controllers.
Currently the NT Hash of the password is recorded when these hashes are calculated and stored. When retrieving the hashes the current value of the NT Hash is checked against the stored NT Hash. This detects password changes that have not updated the password hashes. In this case samba-tool user will ignore the stored hash values.
Being able to obtain the hashed password helps, when they need to be imported into other authentication systems later (see samba-tool user getpassword) or you want to keep the passwords in sync with another system, e.g. an OpenLDAP server (see samba-tool user syncpasswords).
Related command: m[blue]unix password syncm[]
Default: password hash userPassword schemes =
Example: password hash userPassword schemes = CryptSHA256
Example: password hash userPassword schemes = CryptSHA256 CryptSHA512
Example: password hash userPassword schemes = CryptSHA256:rounds=5000 CryptSHA512:rounds=7000
password server (G)
Ideally, this option should not be used, as the default '*' indicates to Samba to determine the best DC to contact dynamically, just as all other hosts in an AD domain do. This allows the domain to be maintained (addition and removal of domain controllers) without modification to the smb.conf file. The cryptographic protection on the authenticated RPC calls used to verify passwords ensures that this default is safe.
It is strongly recommended that you use the default of '*', however if in your particular environment you have reason to specify a particular DC list, then the list of machines in this option must be a list of names or IP addresses of Domain controllers for the Domain. If you use the default of '*', or list several hosts in the password server option then smbd will try each in turn till it finds one that responds. This is useful in case your primary server goes down.
If the list of servers contains both names/IP's and the '*' character, the list is treated as a list of preferred domain controllers, but an auto lookup of all remaining DC's will be added to the list as well. Samba will not attempt to optimize this list by locating the closest DC.
If parameter is a name, it is looked up using the parameter m[blue]name resolve orderm[] and so may resolved by any method and order described in that parameter.
Default: password server = *
Example: password server = NT-PDC, NT-BDC1, NT-BDC2, *
Example: password server = windc.mydomain.com:389 192.168.1.101 *
directory
path (S)
For a printable service offering guest access, the service should be readonly and the path should be world-writeable and have the sticky bit set. This is not mandatory of course, but you probably won't get the results you expect if you do otherwise.
Any occurrences of %u in the path will be replaced with the UNIX username that the client is using on this connection. Any occurrences of %m will be replaced by the NetBIOS name of the machine they are connecting from. These replacements are very useful for setting up pseudo home directories for users.
Note that this path will be based on m[blue]root dirm[] if one was specified.
Default: path =
Example: path = /home/fred
perfcount module (G)
No default
pid directory (G)
Default: pid directory = /run
Example: pid directory = /var/run/
posix locking (S)
Default: posix locking = yes
postexec (S)
An interesting example may be to unmount server resources:
postexec = /etc/umount /cdrom
Default: postexec =
Example: postexec = echo \"%u disconnected from %S from %m (%I)\" >> /tmp/log
exec
preexec (S)
An interesting example is to send the users a welcome message every time they log in. Maybe a message of the day? Here is an example:
preexec = csh -c 'echo \"Welcome to %S!\" | /usr/local/samba/bin/smbclient -M %m -I %I' &
Of course, this could get annoying after a while :-)
See also m[blue]preexec closem[] and m[blue]postexecm[].
Default: preexec =
Example: preexec = echo \"%u connected to %S from %m (%I)\" >> /tmp/log
preexec close (S)
Default: preexec close = no
prefered master
preferred master (G)
If this is set to yes, on startup, nmbd will force an election, and it will have a slight advantage in winning the election. It is recommended that this parameter is used in conjunction with m[blue]domain master = yesm[], so that nmbd can guarantee becoming a domain master.
Use this option with caution, because if there are several hosts (whether Samba servers, Windows 95 or NT) that are preferred master browsers on the same subnet, they will each periodically and continuously attempt to become the local master browser. This will result in unnecessary broadcast traffic and reduced browsing capabilities.
Default: preferred master = auto
prefork backoff increment (G)
Additionally the the backoff for an individual service by using "prefork backoff increment: service name" i.e. "prefork backoff increment:ldap = 2" to set the backoff increment to 2.
If the backoff increment is 2 and the maximum backoff is 5. There will be a zero second delay for the first restart. A two second delay for the second restart. A four second delay for the third and any subsequent restarts
Default: prefork backoff increment = 10
prefork children (G)
This should be set to a small multiple of the number of CPU's available on the server
Additionally the number of prefork children can be specified for an individual service by using "prefork children: service name" i.e. "prefork children:ldap = 8" to set the number of ldap worker processes.
Default: prefork children = 4
prefork maximum backoff (G)
Default: prefork maximum backoff = 120
preload modules (G)
Default: preload modules =
Example: preload modules = /usr/lib/samba/passdb/mysql.so
preserve case (S)
See the section on NAME MANGLING for a fuller discussion.
Default: preserve case = yes
print ok
printable (S)
Note that a printable service will ALWAYS allow writing to the service path (user privileges permitting) via the spooling of print data. The m[blue]read onlym[] parameter controls only non-printing access to the resource.
Default: printable = no
printcap cache time (G)
Setting this parameter to 0 disables any rescanning for new or removed printers after the initial startup.
Default: printcap cache time = 750
Example: printcap cache time = 600
printcap
printcap name (G)
To use the CUPS printing interface set printcap name = cups. This should be supplemented by an additional setting m[blue]printing = cupsm[] in the [global] section. printcap name = cups will use the "dummy" printcap created by CUPS, as specified in your CUPS configuration file.
On System V systems that use lpstat to list available printers you can use printcap name = lpstat to automatically obtain lists of available printers. This is the default for systems that define SYSV at configure time in Samba (this includes most System V based systems). If printcap name is set to lpstat on these systems then Samba will launch lpstat -v and attempt to parse the output to obtain a printer list.
A minimal printcap file would look something like this:
print1|My Printer 1 print2|My Printer 2 print3|My Printer 3 print4|My Printer 4 print5|My Printer 5
where the '|' separates aliases of a printer. The fact that the second alias has a space in it gives a hint to Samba that it's a comment.
Example: printcap name = /etc/myprintcap
print command (S)
The print command is simply a text string. It will be used verbatim after macro substitutions have been made:
%s, %f - the path to the spool file name
%p - the appropriate printer name
%J - the job name as transmitted by the client.
%c - The number of printed pages of the spooled job (if known).
%z - the size of the spooled print job (in bytes)
The print command MUST contain at least one occurrence of %s or %f - the %p is optional. At the time a job is submitted, if no printer name is supplied the %p will be silently removed from the printer command.
If specified in the [global] section, the print command given will be used for any printable service that does not have its own print command specified.
If there is neither a specified print command for a printable service nor a global print command, spool files will be created but not processed and (most importantly) not removed.
Note that printing may fail on some UNIXes from the nobody account. If this happens then create an alternative guest account that can print and set the m[blue]guest accountm[] in the [global] section.
You can form quite complex print commands by realizing that they are just passed to a shell. For example the following will log a print job, print the file, then remove it. Note that ';' is the usual separator for command in shell scripts.
print command = echo Printing %s >> /tmp/print.log; lpr -P %p %s; rm %s
You may have to vary this command considerably depending on how you normally print files on your system. The default for the parameter varies depending on the setting of the m[blue]printingm[] parameter.
Default: For printing = BSD, AIX, QNX, LPRNG or PLP :
print command = lpr -r -P%p %s
For printing = SYSV or HPUX :
print command = lp -c -d%p %s; rm %s
For printing = SOFTQ :
print command = lp -d%p -s %s; rm %s
For printing = CUPS : If SAMBA is compiled against libcups, then m[blue]printcap = cupsm[] uses the CUPS API to submit jobs, etc. Otherwise it maps to the System V commands with the -oraw option for printing, i.e. it uses lp -c -d%p -oraw; rm %s. With printing = cups, and if SAMBA is compiled against libcups, any manually set print command will be ignored.
No default
Example: print command = /usr/local/samba/bin/myprintscript %p %s
printer
printer name (S)
If specified in the [global] section, the printer name given will be used for any printable service that does not have its own printer name specified.
The default value of the m[blue]printer namem[] may be lp on many systems.
Default: printer name =
Example: printer name = laserwriter
printing (S)
Currently nine printing styles are supported. They are BSD, AIX, LPRNG, PLP, SYSV, HPUX, QNX, SOFTQ, CUPS and IPRINT.
Be aware that CUPS and IPRINT are only available if the CUPS development library was available at the time Samba was compiled or packaged.
To see what the defaults are for the other print commands when using the various options use the testparm(1) program.
This option can be set on a per printer basis. Please be aware however, that you must place any of the various printing commands (e.g. print command, lpq command, etc...) after defining the value for the printing option since it will reset the printing commands to default values.
See also the discussion in the [printers] section.
See testparm -v. for the default value on your system
Default: printing = # Depends on the operating system
printjob username (S)
Default: printjob username = %U
Example: printjob username = %D\%U
print notify backchannel (S)
Default: print notify backchannel = no
private directory
private dir (G)
Default: private dir = /var/lib/samba/private
queuepause command (S)
This command should be a program or script which takes a printer name as its only parameter and stops the printer queue, such that no longer jobs are submitted to the printer.
This command is not supported by Windows for Workgroups, but can be issued from the Printers window under Windows 95 and NT.
If a %p is given then the printer name is put in its place. Otherwise it is placed at the end of the command.
Note that it is good practice to include the absolute path in the command as the PATH may not be available to the server.
Default: queuepause command = # determined by printing parameter
Example: queuepause command = disable %p
queueresume command (S)
This command should be a program or script which takes a printer name as its only parameter and resumes the printer queue, such that queued jobs are resubmitted to the printer.
This command is not supported by Windows for Workgroups, but can be issued from the Printers window under Windows 95 and NT.
If a %p is given then the printer name is put in its place. Otherwise it is placed at the end of the command.
Note that it is good practice to include the absolute path in the command as the PATH may not be available to the server.
Default: queueresume command = # determined by printing parameter
Example: queueresume command = enable %p
raw NTLMv2 auth (G)
That is, in the future, the current default of raw NTLMv2 auth = no will be the enforced behaviour.
This parameter determines whether or not smbd(8) will allow SMB1 clients without extended security (without SPNEGO) to use NTLMv2 authentication.
If this option, lanman auth and ntlm auth are all disabled, then only clients with SPNEGO support will be permitted. That means NTLMv2 is only supported within NTLMSSP.
Default: raw NTLMv2 auth = no
read list (S)
Default: read list =
Example: read list = mary, @students
read only (S)
If this parameter is yes, then users of a service may not create or modify files in the service's directory.
Note that a printable service (printable = yes) will ALWAYS allow writing to the directory (user privileges permitting), but only via spooling operations.
Default: read only = yes
read raw (G)
If enabled, raw reads allow reads of 65535 bytes in one packet. This typically provides a major performance benefit for some very, very old clients.
However, some clients either negotiate the allowable block size incorrectly or are incapable of supporting larger block sizes, and for these clients you may need to disable raw reads.
In general this parameter should be viewed as a system tuning tool and left severely alone.
Default: read raw = yes
realm (G)
Default: realm =
Example: realm = mysambabox.mycompany.com
registry shares (G)
Note that this parameter defaults to no, but it is set to yes when config backend is set to registry.
Default: registry shares = no
Example: registry shares = yes
reject md5 clients (G)
You can set this to yes if all domain members support aes. This will prevent downgrade attacks.
This option takes precedence to the 'allow nt4 crypto' option.
Default: reject md5 clients = no
reject md5 servers (G)
The following flags will be required NETLOGON_NEG_ARCFOUR, NETLOGON_NEG_SUPPORTS_AES, NETLOGON_NEG_PASSWORD_SET2 and NETLOGON_NEG_AUTHENTICATED_RPC.
You can set this to yes if all domain controllers support aes. This will prevent downgrade attacks.
The behavior can be controlled per netbios domain by using 'reject md5 servers:NETBIOSDOMAIN = yes' as option.
This option takes precedence to the m[blue]require strong keym[] option.
Default: reject md5 servers = no
remote announce (G)
This is useful if you want your Samba server to appear in a remote workgroup for which the normal browse propagation rules don't work. The remote workgroup can be anywhere that you can send IP packets to.
For example:
remote announce = 192.168.2.255/SERVERS 192.168.4.255/STAFF
the above line would cause nmbd to announce itself to the two given IP addresses using the given workgroup names. If you leave out the workgroup name, then the one given in the m[blue]workgroupm[] parameter is used instead.
The IP addresses you choose would normally be the broadcast addresses of the remote networks, but can also be the IP addresses of known browse masters if your network config is that stable.
See the chapter on Network Browsing in the Samba-HOWTO book.
Default: remote announce =
remote browse sync (G)
This is useful if you want your Samba server and all local clients to appear in a remote workgroup for which the normal browse propagation rules don't work. The remote workgroup can be anywhere that you can send IP packets to.
For example:
remote browse sync = 192.168.2.255 192.168.4.255
the above line would cause nmbd to request the master browser on the specified subnets or addresses to synchronize their browse lists with the local server.
The IP addresses you choose would normally be the broadcast addresses of the remote networks, but can also be the IP addresses of known browse masters if your network config is that stable. If a machine IP address is given Samba makes NO attempt to validate that the remote machine is available, is listening, nor that it is in fact the browse master on its segment.
The m[blue]remote browse syncm[] may be used on networks where there is no WINS server, and may be used on disjoint networks where each network has its own WINS server.
Default: remote browse sync =
rename user script (G)
When a user with admin authority or SeAddUserPrivilege rights renames a user (e.g.: from the NT4 User Manager for Domains), this script will be run to rename the POSIX user. Two variables, %uold and %unew, will be substituted with the old and new usernames, respectively. The script should return 0 upon successful completion, and nonzero otherwise.
require strong key (G)
The following flags will be required NETLOGON_NEG_STRONG_KEYS, NETLOGON_NEG_ARCFOUR and NETLOGON_NEG_AUTHENTICATED_RPC.
You can set this to no if some domain controllers only support des. This might allows weak crypto to be negotiated, may via downgrade attacks.
The behavior can be controlled per netbios domain by using 'require strong key:NETBIOSDOMAIN = no' as option.
Note for active directory domain this option is hardcoded to 'yes'
This option yields precedence to the m[blue]reject md5 serversm[] option.
This option takes precedence to the m[blue]client schannelm[] option.
Default: require strong key = yes
reset on zero vc (G)
Default: reset on zero vc = no
restrict anonymous (G)
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\RestrictAnonymous
The option also affects the browse option which is required by legacy clients which rely on Netbios browsing. While modern Windows version should be fine with restricting the access there could still be applications relying on anonymous access.
Setting m[blue]restrict anonymous = 1m[] will disable anonymous SAMR access.
Setting m[blue]restrict anonymous = 2m[] will, in addition to restricting SAMR access, disallow anonymous connections to the IPC$ share in general. Setting m[blue]guest ok = yesm[] on any share will remove the security advantage.
Default: restrict anonymous = 0
root
root dir
root directory (G)
Adding a root directory entry other than "/" adds an extra level of security, but at a price. It absolutely ensures that no access is given to files not in the sub-tree specified in the root directory option, including some files needed for complete operation of the server. To maintain full operability of the server you will need to mirror some system files into the root directory tree. In particular you will need to mirror /etc/passwd (or a subset of it), and any binaries or configuration files needed for printing (if required). The set of files that must be mirrored is operating system dependent.
Default: root directory =
Example: root directory = /homes/smb
root postexec (S)
Default: root postexec =
root preexec (S)
Default: root preexec =
root preexec close (S)
Default: root preexec close = no
rpc big endian (G)
If it is disabled, data will be transferred in little endian.
The behaviour is independent of the endianness of the host machine.
Default: rpc big endian = no
rpc_daemon:DAEMON (G)
Two possible values are currently supported:
disabled
fork
The classic method is to run rpc services as internal daemons embedded in smbd, therefore the external daemons are disabled by default.
Choosing the fork option will cause samba to fork a separate process for each daemon configured this way. Each daemon may in turn fork a number of children used to handle requests from multiple smbds and direct tcp/ip connections (if the Endpoint Mapper is enabled). Communication with smbd happens over named pipes and require that said pipes are forward to the external daemon (see m[blue]rpc_serverm[]).
Forked RPC Daemons support dynamically forking children to handle connections. The heuristics about how many children to keep around and how fast to allow them to fork and also how many clients each child is allowed to handle concurrently is defined by parametrical options named after the daemon. Five options are currently supported:
prefork_min_children
prefork_max_children
prefork_spawn_rate
prefork_max_allowed_clients
prefork_child_min_life
To set one of these options use the following syntax:
daemonname:prefork_min_children = 5
Samba includes separate daemons for spoolss, lsarpc/lsass, netlogon, samr, FSRVP and mdssvc(Spotlight). Currently five daemons are available and they are called:
epmd
lsasd
spoolssd
fssd
mdssd
Example:
rpc_daemon:spoolssd = fork
Default: rpc_daemon:DAEMON = disabled
rpc_server:SERVER (G)
This option can be set for each available rpc service in Samba. The following list shows all available pipe names services you can modify with this option.
The classic method is to run every pipe as an internal function embedded in smbd. The defaults may vary depending on the service.
Choosing the external option allows one to run a separate daemon or even a completely independent (3rd party) server capable of interfacing with samba via the MS-RPC interface over named pipes.
Currently in Samba3 we support four daemons, spoolssd, epmd, lsasd and mdssd. These daemons can be enabled using the rpc_daemon option. For spoolssd you have to enable the daemon and proxy the named pipe with:
Examples:
rpc_daemon:lsasd = fork
rpc_server:lsarpc = external
rpc_server:samr = external
rpc_server:netlogon = external
rpc_server:spoolss = external
rpc_server:epmapper = disabled
rpc_daemon:mdssd = fork
rpc_server:mdssvc = external
There is one special option which allows you to enable rpc services to listen for ncacn_ip_tcp connections too. Currently this is only used for testing and doesn't scale!
rpc_server:tcpip = yes
Default: rpc_server:SERVER = embedded
rpc server dynamic port range (G)
This applies to RPC servers in all server roles.
Default: rpc server dynamic port range = 49152-65535
rpc server port (G)
This controls the default port for all protocols, except for NETLOGON.
If unset, the first available port from m[blue]rpc server dynamic port rangem[] is used, e.g. 49152.
The NETLOGON server will use the next available port, e.g. 49153. To change this port use (eg) rpc server port:netlogon = 4000.
Furthermore, all RPC servers can have the port they use specified independenty, with (for example) rpc server port:drsuapi = 5000.
This option applies currently only when samba(8) runs as an active directory domain controller.
The default value 0 causes Samba to select the first available port from m[blue]rpc server dynamic port rangem[].
Default: rpc server port = 0
samba kcc command (G)
It should not be necessary to modify this option except for testing purposes or if the samba_kcc was installed in a non-default location.
Default: samba kcc command = /builddir/build/BUILD/samba-4.14.2/source4/scripting/bin/samba_kcc
Example: samba kcc command = /usr/local/bin/kcc
security (G)
The default is security = user, as this is the most common setting, used for a standalone file server or a DC.
The alternatives are security = ads or security = domain, which support joining Samba to a Windows domain
You should use security = user and m[blue]map to guestm[] if you want to mainly setup shares without a password (guest shares). This is commonly used for a shared printer server.
The different settings will now be explained.
SECURITY = AUTO
This is the default security setting in Samba, and causes Samba to consult the m[blue]server rolem[] parameter (if set) to determine the security mode.
SECURITY = USER
If m[blue]server rolem[] is not specified, this is the default security setting in Samba. With user-level security a client must first "log-on" with a valid username and password (which can be mapped using the m[blue]username mapm[] parameter). Encrypted passwords (see the m[blue]encrypted passwordsm[] parameter) can also be used in this security mode. Parameters such as m[blue]userm[] and m[blue]guest onlym[] if set are then applied and may change the UNIX user to use on this connection, but only after the user has been successfully authenticated.
Note that the name of the resource being requested is not sent to the server until after the server has successfully authenticated the client. This is why guest shares don't work in user level security without allowing the server to automatically map unknown users into the m[blue]guest accountm[]. See the m[blue]map to guestm[] parameter for details on doing this.
SECURITY = DOMAIN
This mode will only work correctly if net(8) has been used to add this machine into a Windows NT Domain. It expects the m[blue]encrypted passwordsm[] parameter to be set to yes. In this mode Samba will try to validate the username/password by passing it to a Windows NT Primary or Backup Domain Controller, in exactly the same way that a Windows NT Server would do.
Note that a valid UNIX user must still exist as well as the account on the Domain Controller to allow Samba to have a valid UNIX account to map file access to.
Note that from the client's point of view security = domain is the same as security = user. It only affects how the server deals with the authentication, it does not in any way affect what the client sees.
Note that the name of the resource being requested is not sent to the server until after the server has successfully authenticated the client. This is why guest shares don't work in user level security without allowing the server to automatically map unknown users into the m[blue]guest accountm[]. See the m[blue]map to guestm[] parameter for details on doing this.
See also the m[blue]password serverm[] parameter and the m[blue]encrypted passwordsm[] parameter.
SECURITY = ADS
In this mode, Samba will act as a domain member in an ADS realm. To operate in this mode, the machine running Samba will need to have Kerberos installed and configured and Samba will need to be joined to the ADS realm using the net utility.
Note that this mode does NOT make Samba operate as a Active Directory Domain Controller.
Note that this forces m[blue]require strong key = yesm[] and m[blue]client schannel = yesm[] for the primary domain.
Read the chapter about Domain Membership in the HOWTO for details.
Default: security = AUTO
Example: security = DOMAIN
security mask (S)
No default
max protocol
protocol
server max protocol (G)
Possible values are :
Default: server max protocol = SMB3
Example: server max protocol = LANMAN1
min protocol
server min protocol (G)
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol unless you have legacy clients which are SMB1 capable only.
See Related command: m[blue]server max protocolm[] for a full list of available protocols.
Default: server min protocol = SMB2_02
Example: server min protocol = NT1
server multi channel support (G)
This parameter was added with version 4.4.
Warning: Note that this feature is still considered experimental. Use it at your own risk: Even though it may seem to work well in testing, it may result in data corruption under some race conditions. Future releases may improve this situation.
Due to dependencies to kernel APIs of Linux or FreeBSD, it's only possible to use this feature on Linux and FreeBSD for now. For testing this restriction can be overwritten by specifying force:server multi channel support=yes in addition.
Default: server multi channel support = no
server role (G)
The default is server role = auto, as causes Samba to operate according to the m[blue]securitym[] setting, or if not specified as a simple file server that is not connected to any domain.
The alternatives are server role = standalone or server role = member server, which support joining Samba to a Windows domain, along with server role = domain controller, which run Samba as a Windows domain controller.
You should use server role = standalone and m[blue]map to guestm[] if you want to mainly setup shares without a password (guest shares). This is commonly used for a shared printer server.
SERVER ROLE = AUTO
This is the default server role in Samba, and causes Samba to consult the m[blue]securitym[] parameter (if set) to determine the server role, giving compatible behaviours to previous Samba versions.
SERVER ROLE = STANDALONE
If m[blue]securitym[] is also not specified, this is the default security setting in Samba. In standalone operation, a client must first "log-on" with a valid username and password (which can be mapped using the m[blue]username mapm[] parameter) stored on this machine. Encrypted passwords (see the m[blue]encrypted passwordsm[] parameter) are by default used in this security mode. Parameters such as m[blue]userm[] and m[blue]guest onlym[] if set are then applied and may change the UNIX user to use on this connection, but only after the user has been successfully authenticated.
SERVER ROLE = MEMBER SERVER
This mode will only work correctly if net(8) has been used to add this machine into a Windows Domain. It expects the m[blue]encrypted passwordsm[] parameter to be set to yes. In this mode Samba will try to validate the username/password by passing it to a Windows or Samba Domain Controller, in exactly the same way that a Windows Server would do.
Note that a valid UNIX user must still exist as well as the account on the Domain Controller to allow Samba to have a valid UNIX account to map file access to. Winbind can provide this.
SERVER ROLE = CLASSIC PRIMARY DOMAIN CONTROLLER
This mode of operation runs a classic Samba primary domain controller, providing domain logon services to Windows and Samba clients of an NT4-like domain. Clients must be joined to the domain to create a secure, trusted path across the network. There must be only one PDC per NetBIOS scope (typcially a broadcast network or clients served by a single WINS server).
SERVER ROLE = CLASSIC BACKUP DOMAIN CONTROLLER
This mode of operation runs a classic Samba backup domain controller, providing domain logon services to Windows and Samba clients of an NT4-like domain. As a BDC, this allows multiple Samba servers to provide redundant logon services to a single NetBIOS scope.
SERVER ROLE = ACTIVE DIRECTORY DOMAIN CONTROLLER
This mode of operation runs Samba as an active directory domain controller, providing domain logon services to Windows and Samba clients of the domain. This role requires special configuration, see the Samba4 HOWTO
Default: server role = AUTO
Example: server role = ACTIVE DIRECTORY DOMAIN CONTROLLER
server schannel (G)
Samba will complain in the log files at log level 0, about the security problem if the option is not set to "yes".
See CVE-2020-1472(ZeroLogon) https://bugzilla.samba.org/show_bug.cgi?id=14497
If you still have legacy domain members use the m[blue]server require schannel:COMPUTERACCOUNTm[] option.
This option yields precedence to the m[blue]server require schannel:COMPUTERACCOUNTm[] option.
Default: server schannel = yes
server require schannel:COMPUTERACCOUNT (G)
Samba will complain in the log files at log level 0, about the security problem if the option is not set to "no", but the related computer is actually using the netlogon secure channel (schannel) feature.
Samba will warn in the log files at log level 5, if a setting is still needed for the specified computer account.
See CVE-2020-1472(ZeroLogon) https://bugzilla.samba.org/show_bug.cgi?id=14497
This option takes precedence to the m[blue]server schannelm[] option.
server require schannel:LEGACYCOMPUTER1$ = no
server require schannel:NASBOX$ = no
server require schannel:LEGACYCOMPUTER2$ = no
No default
server services (G)
An entry in the smb.conf file can either override the previous value completely or entries can be removed from or added to it by prefixing them with + or -.
Default: server services = s3fs, rpc, nbt, wrepl, ldap, cldap, kdc, drepl, winbindd, ntp_signd, kcc, dnsupdate, dns
Example: server services = -s3fs, +smb
server signing (G)
By default, and when smb signing is set to default, smb signing is required when m[blue]server rolem[] is active directory domain controller and disabled otherwise.
When set to auto, SMB1 signing is offered, but not enforced. When set to mandatory, SMB1 signing is required and if set to disabled, SMB signing is not offered either.
For the SMB2 protocol, by design, signing cannot be disabled. In the case where SMB2 is negotiated, if this parameter is set to disabled, it will be treated as auto. Setting it to mandatory will still require SMB2 clients to use signing.
Default: server signing = default
server smb encrypt (S)
Effects for SMB1
This may be set on a per-share basis, but clients may chose to encrypt the entire session, not just traffic to a specific share. If this is set to mandatory then all traffic to a share must be encrypted once the connection has been made to the share. The server would return "access denied" to all non-encrypted requests on such a share. Selecting encrypted traffic reduces throughput as smaller packet sizes must be used (no huge UNIX style read/writes allowed) as well as the overhead of encrypting and signing all the data.
If SMB encryption is selected, Windows style SMB signing (see the m[blue]server signingm[] option) is no longer necessary, as the GSSAPI flags use select both signing and sealing of the data.
When set to auto or default, SMB encryption is offered, but not enforced. When set to mandatory, SMB encryption is required and if set to disabled, SMB encryption can not be negotiated.
Effects for SMB2 and newer
The protocol implementation offers various options:
Note that this allows per-share enforcing to be controlled in Samba differently from Windows: In Windows, RejectUnencryptedAccess is a global setting, and if it is set, all shares with data encryption turned on are automatically enforcing encryption. In order to achieve the same effect in Samba, one has to globally set server smb encrypt to if_required, and then set all shares that should be encrypted to required. Additionally, it is possible in Samba to have some shares with encryption required and some other shares with encryption only desired, which is not possible in Windows.
Default: server smb encrypt = default
server string (G)
It also sets what will appear in browse lists next to the machine name.
A %v will be replaced with the Samba version number.
A %h will be replaced with the hostname.
Default: server string = Samba %v
Example: server string = University of GNUs Samba Server
set primary group script (G)
Default: set primary group script =
Example: set primary group script = /usr/sbin/usermod -g '%g' '%u'
set quota command (G)
This option is only available if Samba was compiled with quota support.
This parameter should specify the path to a script that can set quota for the specified arguments.
The specified script should take the following arguments:
Default: set quota command =
Example: set quota command = /usr/local/sbin/set_quota
share backend (G)
Traditionally, Samba file shares have been configured in the smb.conf file and this is still the default.
At the moment there are no other supported backends.
Default: share backend = classic
share:fake_fscaps (G)
Default: share:fake_fscaps = 0
short preserve case (S)
See the section on NAME MANGLING.
Default: short preserve case = yes
show add printer wizard (G)
Under normal circumstances, the Windows NT/2000 client will open a handle on the printer server with OpenPrinterEx() asking for Administrator privileges. If the user does not have administrative access on the print server (i.e is not root or has granted the SePrintOperatorPrivilege), the OpenPrinterEx() call fails and the client makes another open call with a request for a lower privilege level. This should succeed, however the APW icon will not be displayed.
Disabling the show add printer wizard parameter will always cause the OpenPrinterEx() on the server to fail. Thus the APW icon will never be displayed.
shutdown script (G)
If the connected user possesses the SeRemoteShutdownPrivilege, right, this command will be run as root.
The %z %t %r %f variables are expanded as follows:
#!/bin/bash
time=$2
let time="${time} / 60"
let time="${time} + 1"
/sbin/shutdown $3 $4 +$time $1 &
Shutdown does not return so we need to launch it in background.
Default: shutdown script =
Example: shutdown script = /usr/local/samba/sbin/shutdown %m %t %r %f
smb2 disable lock sequence checking (G)
The [MS-SMB2] specification (under 3.3.5.14 Receiving an SMB2 LOCK Request) documents that a server should do lock sequence if Open.IsResilient or Open.IsDurable or Open.IsPersistent is TRUE or if Connection.Dialect belongs to the SMB 3.x dialect family and Connection.ServerCapabilities includes SMB2_GLOBAL_CAP_MULTI_CHANNEL.
But Windows Server (at least up to v2004) only does these checks for the Open.IsResilient and Open.IsPersistent. That means they do not implement the behavior specified in [MS-SMB2].
By default Samba behaves according to the specification and sends smb2 oplock break notification retries.
Warning: Only enable this option if existing clients can't handle lock sequence checking for handles without Open.IsResilient and Open.IsPersistent. And it turns out that the Windows Server behavior is required.
Note: it's likely that this option will be removed again if future Windows versions change their behavior.
Note: Samba does not implement Open.IsResilient and Open.IsPersistent yet.
Default: smb2 disable lock sequence checking = no
Example: smb2 disable lock sequence checking = yes
smb2 disable oplock break retry (G)
The [MS-SMB2] specification documents that a server should send smb2 oplock break notification retries on all available channel to the given client.
But Windows Server versions (at least up to 2019) do not send smb2 oplock break notification retries on channel failures. That means they do not implement the behavior specified in [MS-SMB2].
By default Samba behaves according to the specification and send smb2 oplock break notification retries.
Warning: Only enable this option if existing clients can't handle possible retries and it turns out that the Windows Server behavior is required.
Note: it's likely that this option gets removed again if future Windows versions change their behavior.
Note: this only applies to oplocks and not SMB2 leases.
Default: smb2 disable oplock break retry = no
Example: smb2 disable oplock break retry = yes
smb2 leases (G)
This is only available with m[blue]oplocks = yesm[] and m[blue]kernel oplocks = nom[].
Note that the write cache won't be used for file handles with a smb2 write lease.
Default: smb2 leases = yes
smb2 max credits (G)
The default is 8192 credits, which is the same as a Windows 2008R2 SMB2 server.
Default: smb2 max credits = 8192
smb2 max read (G)
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect (64KiB for SMB == 2.0, 8MiB for SMB >= 2.1 with LargeMTU). Large MTU is not supported over NBT (tcp port 139).
Default: smb2 max read = 8388608
smb2 max trans (G)
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect (64KiB for SMB == 2.0, 1MiB for SMB >= 2.1 with LargeMTU). Large MTU is not supported over NBT (tcp port 139).
Default: smb2 max trans = 8388608
smb2 max write (G)
The maximum is 8388608 bytes (8MiB), which is the same as a Windows Server 2012 r2.
Please note that the default is 8MiB, but it's limit is based on the smb2 dialect (64KiB for SMB == 2.0, 8MiB for SMB => 2.1 with LargeMTU). Large MTU is not supported over NBT (tcp port 139).
Default: smb2 max write = 8388608
smbd async dosmode (S)
Default: smbd async dosmode = no
smbd getinfo ask sharemode (S)
Default: smbd getinfo ask sharemode = yes
smbd max async dosmode (S)
Default: smbd max async dosmode = aio max threads * 2
smbd profiling level (G)
Possible values are off, count and on.
Default: smbd profiling level = off
Example: smbd profiling level = on
smbd search ask sharemode (S)
Default: smbd search ask sharemode = yes
smb encrypt (S)
Default: smb encrypt = default
smb passwd file (G)
An example of use is:
smb passwd file = /etc/samba/smbpasswd
Default: smb passwd file = /var/lib/samba/private/smbpasswd
smb ports (G)
Default: smb ports = 445 139
socket options (G)
Getting the socket options correct can make a big difference to your performance, but getting them wrong can degrade it by just as much. As with any other low level setting, if you must make changes to it, make small changes and test the effect before making any large changes.
This option allows you to set socket options to be used when talking with the client.
Socket options are controls on the networking layer of the operating systems which allow the connection to be tuned.
This option will typically be used to tune your Samba server for optimal performance for your local network. There is no way that Samba can know what the optimal parameters are for your net, so you must experiment and choose them yourself. We strongly suggest you read the appropriate documentation for your operating system first (perhaps man setsockopt will help).
You may find that on some systems Samba will say "Unknown socket option" when you supply an option. This means you either incorrectly typed it or you need to add an include file to includes.h for your OS. If the latter is the case please send the patch to samba-technical@lists.samba.org.
Any of the supported socket options may be combined in any way you like, as long as your OS allows it.
This is the list of socket options currently settable using this option:
To specify an argument use the syntax SOME_OPTION = VALUE for example SO_SNDBUF = 8192. Note that you must not have any spaces before or after the = sign.
If you are on a local network then a sensible option might be:
socket options = IPTOS_LOWDELAY
If you have a local network then you could try:
socket options = IPTOS_LOWDELAY TCP_NODELAY
If you are on a wide area network then perhaps try setting IPTOS_THROUGHPUT.
Note that several of the options may cause your Samba server to fail completely. Use these options with caution!
Default: socket options = TCP_NODELAY
Example: socket options = IPTOS_LOWDELAY
spn update command (G)
Default: spn update command = /builddir/build/BUILD/samba-4.14.2/source4/scripting/bin/samba_spnupdate
Example: spn update command = /usr/local/sbin/spnupdate
spoolss: architecture (G)
Default: spoolss: architecture = Windows x64
Example: spoolss: architecture = Windows NT x86
spoolss: os_major (G)
Default: spoolss: os_major = 5
Example: spoolss: os_major = 6
spoolss: os_minor (G)
Default: spoolss: os_minor = 0
Example: spoolss: os_minor = 1
spoolss: os_build (G)
Default: spoolss: os_build = 2195
Example: spoolss: os_build = 7601
spoolss_client: os_major (G)
Default: spoolss_client: os_major = 6
spoolss_client: os_minor (G)
Default: spoolss_client: os_minor = 1
spoolss_client: os_build (G)
Default: spoolss_client: os_build = 7007
spotlight (S)
Spotlight has several prerequisites:
The Spotlight RPC service can either be enabled as embedded RPC service:
[Global] m[blue]rpc_server:mdsvc = embeddedm[]
Or it can be run in a separate RPC service daemon:
[Global] m[blue]rpc_server:mdssd = forkm[] m[blue]rpc_server:mdsvc = externalm[]
Default: spotlight = no
spotlight backend (S)
Default: spotlight backend = noindex
stat cache (G)
Default: stat cache = yes
state directory (G)
This option specifies the directory where TDB files containing important persistent data will be stored.
Default: state directory = /var/lib/samba
Example: state directory = /var/run/samba/locks/state
store dos attributes (S)
Default: store dos attributes = yes
strict allocate (S)
This option is really designed for file systems that support fast allocation of large numbers of blocks such as extent-based file systems. On file systems that don't support extents (most notably ext3) this can make Samba slower. When you work with large files over >100MB on file systems without extents you may even run into problems with clients running into timeouts.
When you have an extent based filesystem it's likely that we can make use of unwritten extents which allows Samba to allocate even large amounts of space very fast and you will not see any timeout problems caused by strict allocate. With strict allocate in use you will also get much better out of quota messages in case you use quotas. Another advantage of activating this setting is that it will help to reduce file fragmentation.
To give you an idea on which filesystems this setting might currently be a good option for you: XFS, ext4, btrfs, ocfs2 on Linux and JFS2 on AIX support unwritten extents. On Filesystems that do not support it, preallocation is probably an expensive operation where you will see reduced performance and risk to let clients run into timeouts when creating large files. Examples are ext3, ZFS, HFS+ and most others, so be aware if you activate this setting on those filesystems.
Default: strict allocate = no
strict locking (S)
When strict locking is set to Auto (the default), the server performs file lock checks only on non-oplocked files. As most Windows redirectors perform file locking checks locally on oplocked files this is a good trade off for improved performance.
When strict locking is disabled, the server performs file lock checks only when the client explicitly asks for them.
Well-behaved clients always ask for lock checks when it is important. So in the vast majority of cases, strict locking = Auto or strict locking = no is acceptable.
Default: strict locking = Auto
strict rename (S)
This boolean parameter allows Samba to match the Windows behavior. Setting this to "yes" is a very expensive change, as it forces Samba to travers the entire open file handle database on every directory rename request. In a clustered Samba system the cost is even greater than the non-clustered case.
When set to "no" smbd only checks the local process the client is attached to for open files below a directory being renamed, instead of checking for open files across all smbd processes.
Because of the expense in fully searching the database, the default is "no", and it is recommended to be left that way unless a specific Windows application requires it to be changed.
If the client has requested UNIX extensions (POSIX pathnames) then renames are always allowed and this parameter has no effect.
Default: strict rename = no
strict sync (S)
In Samba 4.7.0, the default for this parameter changed from no to yes to better match the expectations of SMB2/3 clients and improve application safety when running against smbd.
The flush request from SMB2/3 clients is handled asynchronously inside smbd, so leaving the parameter as the default value of yes does not block the processing of other requests to the smbd process.
Legacy Windows applications (such as the Windows 98 explorer shell) seemed to confuse writing buffer contents to the operating system with synchronously writing outstanding data onto stable storage on disk. Changing this parameter to no means that smbd(8) will ignore the Windows applications request to synchronize unwritten data onto disk. Only consider changing this if smbd is serving obsolete SMB1 Windows clients prior to Windows XP (Windows 98 and below). There should be no need to change this setting for normal operations.
Default: strict sync = yes
svcctl list (G)
The administrator must create a directory name svcctl in Samba's $(libdir) and create symbolic links to the init scripts in /etc/init.d/. The name of the links must match the names given as part of the svcctl list.
Default: svcctl list =
Example: svcctl list = cups postfix portmap httpd
sync always (S)
Default: sync always = no
syslog (G)
This parameter sets the threshold for sending messages to syslog. Only messages with debug level less than this value will be sent to syslog. There still will be some logging to log.[sn]mbd even if syslog only is enabled.
The m[blue]loggingm[] parameter should be used instead. When m[blue]loggingm[] is set, it overrides the m[blue]syslogm[] parameter.
Default: syslog = 1
syslog only (G)
The m[blue]loggingm[] parameter should be used instead. When m[blue]loggingm[] is set, it overrides the m[blue]syslog onlym[] parameter.
Default: syslog only = no
template homedir (G)
Default: template homedir = /home/%D/%U
template shell (G)
Default: template shell = /bin/false
time server (G)
Default: time server = no
debug timestamp
timestamp logs (G)
Default: timestamp logs = yes
tls cafile (G)
This path is relative to m[blue]private dirm[] if the path does not start with a /.
Default: tls cafile = tls/ca.pem
tls certfile (G)
This path is relative to m[blue]private dirm[] if the path does not start with a /.
Default: tls certfile = tls/cert.pem
tls crlfile (G)
This path is relative to m[blue]private dirm[] if the path does not start with a /.
Default: tls crlfile =
tls dh params file (G)
This path is relative to m[blue]private dirm[] if the path does not start with a /.
Default: tls dh params file =
tls enabled (G)
Default: tls enabled = yes
tls keyfile (G)
This path is relative to m[blue]private dirm[] if the path does not start with a /.
Default: tls keyfile = tls/key.pem
tls priority (G)
The string is appended to the default priority list of GnuTLS.
The valid options are described in the GNUTLS Priority-Strings documentation at http://gnutls.org/manual/html_node/Priority-Strings.html
The SSL3.0 protocol will be disabled.
Default: tls priority = NORMAL:-VERS-SSL3.0
tls verify peer (G)
When set to no_check the certificate is not verified at all, which allows trivial man in the middle attacks.
When set to ca_only the certificate is verified to be signed from a ca specified in the m[blue]tls ca filem[] option. Setting m[blue]tls ca filem[] to a valid file is required. The certificate lifetime is also verified. If the m[blue]tls crl filem[] option is configured, the certificate is also verified against the ca crl.
When set to ca_and_name_if_available all checks from ca_only are performed. In addition, the peer hostname is verified against the certificate's name, if it is provided by the application layer and not given as an ip address string.
When set to ca_and_name all checks from ca_and_name_if_available are performed. In addition the peer hostname needs to be provided and even an ip address is checked against the certificate's name.
When set to as_strict_as_possible all checks from ca_and_name are performed. In addition the m[blue]tls crl filem[] needs to be configured. Future versions of Samba may implement additional checks.
Default: tls verify peer = as_strict_as_possible
unicode (G)
If this option is set to false, the use of ASCII will be forced.
Default: unicode = yes
unix charset (G)
This is also the charset Samba will use when specifying arguments to scripts that it invokes.
Default: unix charset = UTF-8
Example: unix charset = ASCII
unix extensions (G)
Note if this parameter is turned on, the m[blue]wide linksm[] parameter will automatically be disabled.
See the parameter m[blue]allow insecure wide linksm[] if you wish to change this coupling between the two parameters.
Default: unix extensions = yes
unix password sync (G)
This option has no effect if samba is running as an active directory domain controller, in that case have a look at the m[blue]password hash gpg key idsm[] option and the samba-tool user syncpasswords command.
Default: unix password sync = no
use client driver (S)
The differentiating factor is that under normal circumstances, the NT/2000 client will attempt to open the network printer using MS-RPC. The problem is that because the client considers the printer to be local, it will attempt to issue the OpenPrinterEx() call requesting access rights associated with the logged on user. If the user possesses local administrator rights but not root privilege on the Samba host (often the case), the OpenPrinterEx() call will fail. The result is that the client will now display an "Access Denied; Unable to connect" message in the printer queue window (even though jobs may successfully be printed).
If this parameter is enabled for a printer, then any attempt to open the printer with the PRINTER_ACCESS_ADMINISTER right is mapped to PRINTER_ACCESS_USE instead. Thus allowing the OpenPrinterEx() call to succeed. This parameter MUST not be enabled on a print share which has valid print driver installed on the Samba server.
Default: use client driver = no
use mmap (G)
Default: use mmap = yes
username level (G)
If this parameter is set to non-zero the behavior changes. This parameter is a number that specifies the number of uppercase combinations to try while trying to determine the UNIX user name. The higher the number the more combinations will be tried, but the slower the discovery of usernames will be. Use this parameter when you have strange usernames on your UNIX machine, such as AstrangeUser .
This parameter is needed only on UNIX systems that have case sensitive usernames.
Default: username level = 0
Example: username level = 5
username map (G)
Please note that for user mode security, the username map is applied prior to validating the user credentials. Domain member servers (domain or ads) apply the username map after the user has been successfully authenticated by the domain controller and require fully qualified entries in the map table (e.g. biddle = DOMAIN\foo).
The map file is parsed line by line. Each line should contain a single UNIX username on the left then a '=' followed by a list of usernames on the right. The list of usernames on the right may contain names of the form @group in which case they will match any UNIX username in that group. The special client name '*' is a wildcard and matches any name. Each line of the map file may be up to 1023 characters long.
The file is processed on each line by taking the supplied username and comparing it with each username on the right hand side of the '=' signs. If the supplied name matches any of the names on the right hand side then it is replaced with the name on the left. Processing then continues with the next line.
If any line begins with a '#' or a ';' then it is ignored.
If any line begins with an '!' then the processing will stop after that line if a mapping was done by the line. Otherwise mapping continues with every line being processed. Using '!' is most useful when you have a wildcard mapping line later in the file.
For example to map from the name admin or administrator to the UNIX name root you would use:
root = admin administrator
Or to map anyone in the UNIX group system to the UNIX name sys you would use:
sys = @system
You can have as many mappings as you like in a username map file.
If your system supports the NIS NETGROUP option then the netgroup database is checked before the /etc/group database for matching groups.
You can map Windows usernames that have spaces in them by using double quotes around the name. For example:
tridge = "Andrew Tridgell"
would map the windows username "Andrew Tridgell" to the unix username "tridge".
The following example would map mary and fred to the unix user sys, and map the rest to guest. Note the use of the '!' to tell Samba to stop processing if it gets a match on that line:
!sys = mary fred guest = *
Note that the remapping is applied to all occurrences of usernames. Thus if you connect to \\server\fred and fred is remapped to mary then you will actually be connecting to \\server\mary and will need to supply a password suitable for mary not fred. The only exception to this is the username passed to a Domain Controller (if you have one). The DC will receive whatever username the client supplies without modification.
Also note that no reverse mapping is done. The main effect this has is with printing. Users who have been mapped may have trouble deleting print jobs as PrintManager under WfWg will think they don't own the print job.
Samba versions prior to 3.0.8 would only support reading the fully qualified username (e.g.: DOMAIN\user) from the username map when performing a kerberos login from a client. However, when looking up a map entry for a user authenticated by NTLM[SSP], only the login name would be used for matches. This resulted in inconsistent behavior sometimes even on the same server.
The following functionality is obeyed in version 3.0.8 and later:
When performing local authentication, the username map is applied to the login name before attempting to authenticate the connection.
When relying upon a external domain controller for validating authentication requests, smbd will apply the username map to the fully qualified username (i.e. DOMAIN\user) only after the user has been successfully authenticated.
An example of use is:
username map = /usr/local/samba/lib/users.map
Default: username map = # no username map
username map cache time (G)
The parameter m[blue]username map cache timem[] controls a mapping cache. It specifies the number of seconds a mapping from the username map file or script is to be efficiently cached. The default of 0 means no caching is done.
Default: username map cache time = 0
Example: username map cache time = 60
username map script (G)
Default: username map script =
Example: username map script = /etc/samba/scripts/mapusers.sh
usershare allow guests (G)
Default: usershare allow guests = no
usershare max shares (G)
Default: usershare max shares = 0
usershare owner only (G)
Default: usershare owner only = yes
usershare path (G)
For example, a valid usershare directory might be /usr/local/samba/lib/usershares, set up as follows.
ls -ld /usr/local/samba/lib/usershares/
drwxrwx--T 2 root power_users 4096 2006-05-05 12:27 /usr/local/samba/lib/usershares/
In this case, only members of the group "power_users" can create user defined shares.
Default: usershare path = /var/lib/samba/usershares
usershare prefix allow list (G)
If there is a "usershare prefix deny list" and also a "usershare prefix allow list" the deny list is processed first, followed by the allow list, thus leading to the most restrictive interpretation.
Default: usershare prefix allow list =
Example: usershare prefix allow list = /home /data /space
usershare prefix deny list (G)
If there is a "usershare prefix deny list" and also a "usershare prefix allow list" the deny list is processed first, followed by the allow list, thus leading to the most restrictive interpretation.
Default: usershare prefix deny list =
Example: usershare prefix deny list = /etc /dev /private
usershare template share (G)
The target share may be set to be invalid for real file sharing by setting the parameter "-valid = False" on the template share definition. This causes it not to be seen as a real exported share but to be able to be used as a template for usershares.
Default: usershare template share =
Example: usershare template share = template_share
use sendfile (S)
Default: use sendfile = no
utmp (G)
Due to the requirements of the utmp record, we are required to create a unique identifier for the incoming user. Enabling this option creates an n^2 algorithm to find this number. This may impede performance on large installations.
Default: utmp = no
utmp directory (G)
Default: utmp directory = # Determined automatically
Example: utmp directory = /var/run/utmp
-valid (S)
This option should not be used by regular users but might be of help to developers. Samba uses this option internally to mark shares as deleted.
Default: -valid = yes
valid users (S)
If this is empty (the default) then any user can login. If a username is in both this list and the invalid users list then access is denied for that user.
The current servicename is substituted for %S. This is useful in the [homes] section.
Note: When used in the [global] section this parameter may have unwanted side effects. For example: If samba is configured as a MASTER BROWSER (see local master, os level, domain master, preferred master) this option will prevent workstations from being able to browse the network.
Default: valid users = # No valid users list (anyone can login)
Example: valid users = greg, @pcusers
veto files (S)
Each entry must be a unix path, not a DOS path and must not include the unix directory separator '/'.
Note that the m[blue]case sensitivem[] option is applicable in vetoing files.
One feature of the veto files parameter that it is important to be aware of is Samba's behaviour when trying to delete a directory. If a directory that is to be deleted contains nothing but veto files this deletion will fail unless you also set the m[blue]delete veto filesm[] parameter to yes.
Setting this parameter will affect the performance of Samba, as it will be forced to check all files and directories for a match as they are scanned.
Examples of use include:
; Veto any files containing the word Security, ; any ending in .tmp, and any directory containing the ; word root. veto files = /*Security*/*.tmp/*root*/ ; Veto the Apple specific files that a NetAtalk server ; creates. veto files = /.AppleDouble/.bin/.AppleDesktop/Network Trash Folder/
Default: veto files = # No files or directories are vetoed
veto oplock files (S)
You might want to do this on files that you know will be heavily contended for by clients. A good example of this is in the NetBench SMB benchmark program, which causes heavy client contention for files ending in .SEM. To cause Samba not to grant oplocks on these files you would use the line (either in the [global] section or in the section for the particular NetBench share.
An example of use is:
veto oplock files = /.*SEM/
Default: veto oplock files = # No files are vetoed for oplock grants
vfs object
vfs objects (S)
Default: vfs objects =
Example: vfs objects = extd_audit recycle
volume (S)
Default: volume = # the name of the share
wide links (S)
Note: Turning this parameter on when UNIX extensions are enabled will allow UNIX clients to create symbolic links on the share that can point to files or directories outside restricted path exported by the share definition. This can cause access to areas outside of the share. Due to this problem, this parameter will be automatically disabled (with a message in the log file) if the m[blue]unix extensionsm[] option is on.
See the parameter m[blue]allow insecure wide linksm[] if you wish to change this coupling between the two parameters.
Default: wide links = no
winbind cache time (G)
This does not apply to authentication requests, these are always evaluated in real time unless the m[blue]winbind offline logonm[] option has been enabled.
Default: winbind cache time = 300
winbindd socket directory (G)
Except within automated test scripts, this should not be altered, as the client tools (nss_winbind etc) do not honour this parameter. Client tools must then be advised of the altered path with the WINBINDD_SOCKET_DIR environment variable.
Default: winbindd socket directory = /run/samba/winbindd
winbind enum groups (G)
winbind enum users (G)
winbind expand groups (G)
This option also affects the return of non nested group memberships of Windows domain users. With the new default "winbind expand groups = 0" winbind does not query group memberships at all.
Be aware that a high value for this parameter can result in system slowdown as the main parent winbindd daemon must perform the group unrolling and will be unable to answer incoming NSS or authentication requests during this time.
The default value was changed from 1 to 0 with Samba 4.2. Some broken applications (including some implementations of newgrp and sg) calculate the group memberships of users by traversing groups, such applications will require "winbind expand groups = 1". But the new default makes winbindd more reliable as it doesn't require SAMR access to domain controllers of trusted domains.
Default: winbind expand groups = 0
winbind:ignore domains (G)
Default: winbind:ignore domains =
Example: winbind:ignore domains = DOMAIN1, DOMAIN2
winbind max clients (G)
Default: winbind max clients = 200
winbind max domain connections (G)
Note that if m[blue]winbind offline logonm[] is set to Yes, then only one DC connection is allowed per domain, regardless of this setting.
Default: winbind max domain connections = 1
Example: winbind max domain connections = 10
winbind nested groups (G)
Default: winbind nested groups = yes
winbind normalize names (G)
This feature also enables the name aliasing API which can be used to make domain user and group names to a non-qualified version. Please refer to the manpage for the configured idmap and nss_info plugin for the specifics on how to configure name aliasing for a specific configuration. Name aliasing takes precedence (and is mutually exclusive) over the whitespace replacement mechanism discussed previously.
Default: winbind normalize names = no
Example: winbind normalize names = yes
winbind nss info (G)
Note that for the idmap backend idmap_ad you need to configure those settings in the idmap configuration section. Make sure to consult the documentation of the idmap backend that you are using.
Default: winbind nss info = template
Example: winbind nss info = sfu
winbind offline logon (G)
Default: winbind offline logon = no
Example: winbind offline logon = yes
winbind reconnect delay (G)
Default: winbind reconnect delay = 30
winbind refresh tickets (G)
Default: winbind refresh tickets = no
Example: winbind refresh tickets = yes
winbind request timeout (G)
Default: winbind request timeout = 60
winbind rpc only (G)
Default: winbind rpc only = no
winbind scan trusted domains (G)
The construction of that global list is not reliable and often incomplete in complex trust setups. In most situations the list is not needed any more for winbindd to operate correctly. E.g. for plain file serving via SMB using a simple idmap setup with autorid, tdb or ad. However some more complex setups require the list, e.g. if you specify idmap backends for specific domains. Some pam_winbind setups may also require the global list.
If you have a setup that doesn't require the global list, you should set m[blue]winbind scan trusted domains = nom[].
Default: winbind scan trusted domains = yes
winbind sealed pipes (G)
The behavior can be controlled per netbios domain by using 'winbind sealed pipes:NETBIOSDOMAIN = no' as option.
Default: winbind sealed pipes = yes
winbind separator (G)
Please note that setting this parameter to + causes problems with group membership at least on glibc systems, as the character + is used as a special character for NIS in /etc/group.
Default: winbind separator = \
Example: winbind separator = +
winbind use default domain (G)
This option should be avoided if possible. It can cause confusion about responsibilities for a user or group. In many situations it is not clear whether winbind or /etc/passwd should be seen as authoritative for a user, likewise for groups.
Default: winbind use default domain = no
Example: winbind use default domain = yes
winbind use krb5 enterprise principals (G)
winbindd (at least on a domain member) is never be able to have a complete picture of the trust topology (which is managed by the DCs). There might be uPNSuffixes and msDS-SPNSuffixes values, which don't belong to any AD domain at all.
With m[blue]winbind scan trusted domains = nom[] winbindd don't even get an incomplete picture of the topology.
It is not really required to know about the trust topology. We can just rely on the [K]DCs of our primary domain (e.g. PRIMARY.A.EXAMPLE.COM) and use enterprise principals e.g. upnfromB@B.EXAMPLE.COM@PRIMARY.A.EXAMPLE.COM and follow the WRONG_REALM referrals in order to find the correct DC. The final principal might be userfromB@INTERNALB.EXAMPLE.PRIVATE.
With m[blue]winbind use krb5 enterprise principals = yesm[] winbindd enterprise principals will be used.
Default: winbind use krb5 enterprise principals = no
Example: winbind use krb5 enterprise principals = yes
winsdb:local_owner (G)
No default
winsdb:dbnosync (G)
Default: winsdb:dbnosync = no
wins hook (G)
The wins hook parameter specifies the name of a script or executable that will be called as follows:
wins_hook operation name nametype ttl IP_list
No default
wins proxy (G)
Default: wins proxy = no
wins server (G)
You should point this at your WINS server if you have a multi-subnetted network.
If you want to work in multiple namespaces, you can give every wins server a 'tag'. For each tag, only one (working) server will be queried for a name. The tag should be separated from the ip address by a colon.
Default: wins server =
Example: wins server = mary:192.9.200.1 fred:192.168.3.199 mary:192.168.2.61 # For this example when querying a certain name, 192.19.200.1 will be asked first and if that doesn't respond 192.168.2.61. If either of those doesn't know the name 192.168.3.199 will be queried.
Example: wins server = 192.9.200.1 192.168.2.61
wins support (G)
Default: wins support = no
workgroup (G)
Default: workgroup = WORKGROUP
Example: workgroup = MYGROUP
wreplsrv:periodic_interval (G)
Default: wreplsrv:periodic_interval = 15
wreplsrv:propagate name releases (G)
Default: wreplsrv:propagate name releases = no
wreplsrv:scavenging_interval (G)
No default
wreplsrv:tombstone_extra_timeout (G)
Default: wreplsrv:tombstone_extra_timeout = 259200
wreplsrv:tombstone_interval (G)
Default: wreplsrv:tombstone_interval = 518400
wreplsrv:tombstone_timeout (G)
Default: wreplsrv:tombstone_timeout = 86400
wreplsrv:verify_interval (G)
Default: wreplsrv:verify_interval = 2073600
writable
write ok
writeable (S)
Default: writeable = no
write list (S)
Note that if a user is in both the read list and the write list then they will be given write access.
Default: write list =
Example: write list = admin, root, @staff
write raw (G)
If enabled, raw writes allow writes of 65535 bytes in one packet. This typically provides a major performance benefit for some very, very old clients.
However, some clients either negotiate the allowable block size incorrectly or are incapable of supporting larger block sizes, and for these clients you may need to disable raw writes.
In general this parameter should be viewed as a system tuning tool and left severely alone.
Default: write raw = yes
wtmp directory (G)
By default this is not set, meaning the system will use whatever utmp file the native system is set to use (usually /var/run/wtmp on Linux).
Default: wtmp directory =
Example: wtmp directory = /var/log/wtmp
Although the configuration file permits service names to contain spaces, your client software may not. Spaces will be ignored in comparisons anyway, so it shouldn't be a problem - but be aware of the possibility.
On a similar note, many clients - especially DOS clients - limit service names to eight characters. smbd(8) has no such limitation, but attempts to connect from such clients will fail if they truncate the service names. For this reason you should probably keep your service names down to eight characters in length.
Use of the [homes] and [printers] special sections make life for an administrator easy, but the various combinations of default attributes can be tricky. Take extreme care when designing these sections. In particular, ensure that the permissions on spool directories are correct.
This man page is part of version 4.14.2 of the Samba suite.
samba(7), smbpasswd(8), smbd(8), nmbd(8), winbindd(8), samba(8), samba-tool(8), smbclient(1), nmblookup(1), testparm(1).
The original Samba software and related utilities were created by Andrew Tridgell. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed.