trusty (5) sysctl.d.5.gz

NAME

       sysctl.d - Configure kernel parameters at boot

SYNOPSIS

       /etc/sysctl.d/*.conf

       /run/sysctl.d/*.conf

       /usr/lib/sysctl.d/*.conf

DESCRIPTION

       At boot, systemd-sysctl.service(8) reads configuration files from the above directories to configure
       sysctl(8) kernel parameters.

CONFIGURATION FORMAT

       The configuration files contain a list of variable assignments, separated by newlines. Empty lines and
       lines whose first non-whitespace character is # or ; are ignored.

       Note that both / and . are accepted as label separators within sysctl variable names.
       kernel.domainname=foo and kernel/domainname=foo hence are entirely equivalent.

       Each configuration file shall be named in the style of program.conf. Files in /etc/ override files with
       the same name in /usr/lib/ and /run/. Files in /run/ override files with the same name in /usr/lib/.
       Packages should install their configuration files in /usr/lib/. Files in /etc/ are reserved for the local
       administrator, who may use this logic to override the configuration files installed by vendor packages.
       All configuration files are sorted by their filename in alphabetical order, regardless in which of the
       directories they reside, to guarantee that a specific configuration file takes precedence over another
       file with an alphabetically later name, if both files contain the same variable setting.

       If the administrator wants to disable a configuration file supplied by the vendor the recommended way is
       to place a symlink to /dev/null in /etc/sysctl.d/ bearing the same file name.

EXAMPLE

       Example 1. /etc/sysctl.d/domain-name.conf example:

           # Set kernel YP domain name
           kernel.domainname=example.com

SEE ALSO

       systemd(1), systemd-sysctl.service(8), systemd-delta(1), sysctl(8), sysctl.conf(5)