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.
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)