SYSCTL.CONF

Section: File Formats (5)
Updated: 2020-06-04
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NAME

sysctl.conf - sysctl preload/configuration file

DESCRIPTION

sysctl.conf is a simple file containing sysctl values to be read in and set by sysctl. The syntax is simply as follows:

# comment
; comment

token = value

Note that blank lines are ignored, and whitespace before and after a token or value is ignored, although a value can contain whitespace within. Lines which begin with a # or ; are considered comments and ignored.

If a line begins with a single -, any attempts to set the value that fail will be ignored.

NOTES

As the /etc/sysctl.conf file is used to override default kernel parameter values, only a small number of parameters is predefined in the file. Use /sbin/sysctl -a or follow sysctl(8) to list all possible parameters. The description of individual parameters can be found in the kernel documentation.

EXAMPLE

# sysctl.conf sample
#
  kernel.domainname = example.com
; this one has a space which will be written to the sysctl!
  kernel.modprobe = /sbin/mod probe

FILES

/etc/sysctl.d/*.conf
/run/sysctl.d/*.conf
/usr/local/lib/sysctl.d/*.conf
/usr/lib/sysctl.d/*.conf
/lib/sysctl.d/*.conf
/etc/sysctl.conf

The paths where sysctl preload files usually exist. See also sysctl option --system.

AUTHOR

George Staikos

REPORTING BUGS

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