sysctl.conf - sysctl preload/configuration file

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.

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.

# sysctl.conf sample

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


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


George Staikos

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2020-06-04 procps-ng