SYSCTL.CONF(5) File Formats Manual SYSCTL.CONF(5)
NAME
sysctl.conf - Linux kernel configuration parameters
DESCRIPTION
sysctl.conf is a set of configuration files that contain Linux kernel
configuration parameters to be read and set by sysctl(8).
This man page describes the configuration files for procps sysctl. If
you are using systemd-sysctl(8), refer to sysctl.d(5) and note that it
won't use the file /etc/sysctl.conf.
Configuration Format
Each line of a file read by procps sysctl describes a kernel parameter
in the following format.
token = value
Blank lines and lines that start with “#” or “;” are ignored.
If a line begins with a single “-”, a failing attempt to set the value
is ignored.
FILES
procps sysctl, when run with the --system option, reads files from di-
rectories in the order shown below.
/etc/sysctl.d/*.conf
/run/sysctl.d/*.conf
/usr/local/lib/sysctl.d/*.conf
/usr/lib/sysctl.d/*.conf
/lib/sysctl.d/*.conf
Finally, procps sysctl reads /etc/sysctl.conf. This file is not used by
systemd-sysctl, which means that some kernel parameters are not set de-
pending on the implementation of sysctl that is installed.
BUGS
The maximum supported length of value is 4096 characters due to a limi-
tation on /proc entry length in the Linux kernel.
EXAMPLES
#
#
kernel.domainname = example.com
; A value containing a space is written to the sysctl.
kernel.modprobe = /sbin/mod probe
SEE ALSO
sysctl.d(5), sysctl(8), systemd-sysctl(8)
procps-ng 2024-10-24 SYSCTL.CONF(5)
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