blkmapd

Section: Maintenance Commands (8)
Updated: 11 August 2011
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NAME

blkmapd - pNFS block layout mapping daemon  

SYNOPSIS

blkmapd [-h] [-d] [-f]  

DESCRIPTION

The blkmapd daemon performs device discovery and mapping for the parallel NFS (pNFS) block layout client [RFC5663].

The pNFS block layout protocol builds a complex storage hierarchy from a set of simple volumes. These simple volumes are addressed by content, using a signature on the volume to uniquely name each one. The daemon locates a volume by examining each block device in the system for the given signature.

The topology typically consists of a hierarchy of volumes built by striping, slicing, and concatenating the simple volumes. The blkmapd daemon uses the device-mapper driver to construct logical devices that reflect the server topology, and passes these devices to the kernel for use by the pNFS block layout client.  

OPTIONS

-h
Display usage message.
-d
Performs device discovery only then exits.
-f
Runs blkmapd in the foreground and sends output to stderr (as opposed to syslogd)
 

CONFIGURATION FILE

The blkmapd daemon recognizes the following value from the [general] section of the /etc/nfs.conf configuration file:
pipefs-directory
Tells blkmapd where to look for the rpc_pipefs filesystem. The default value is /var/lib/nfs/rpc_pipefs.
 

SEE ALSO

nfs(5), dmsetup(8), nfs.conf(5)

RFC 5661 for the NFS version 4.1 specification.
RFC 5663 for the pNFS block layout specification.  

AUTHORS


Haiying Tang <Tang_Haiying@emc.com>
Jim Rees <rees@umich.edu>


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
CONFIGURATION FILE
SEE ALSO
AUTHORS