xref: /freebsd/share/man/man5/sysctl.conf.5 (revision 57718be8fa0bd5edc11ab9a72e68cc71982939a6)
1.\" Copyright (c) 1999 Chris Costello <chris@FreeBSD.org>
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25.\" $FreeBSD$
26.\"
27.Dd December 30, 1999
28.Dt SYSCTL.CONF 5
29.Os
30.Sh NAME
31.Nm sysctl.conf
32.Nd kernel state defaults
33.Sh DESCRIPTION
34The
35.Pa /etc/sysctl.conf
36file is read in when the system goes into multi-user mode to set default
37settings for the kernel.
38The
39.Pa /etc/sysctl.conf
40is in the format of the
41.Xr sysctl 8
42command, i.e.\&
43.Bd -literal -offset indent
44sysctl_mib=value
45.Ed
46.Pp
47Comments are denoted by a
48.Dq #
49at the beginning of a line.
50Comments can also exist at the end of a line,
51as seen in the
52.Sx EXAMPLES
53section, below.
54.Sh FILES
55.Bl -tag -width /etc/sysctl.conf -compact
56.It Pa /etc/sysctl.conf
57Initial settings for
58.Xr sysctl 8 .
59.El
60.Sh EXAMPLES
61To turn off logging of programs that exit due to fatal signals you may use
62a configuration like
63.Bd -literal -offset indent
64# Configure logging.
65kern.logsigexit=0	# Do not log fatal signal exits (e.g. sig 11)
66.Ed
67.Sh SEE ALSO
68.Xr rc.conf 5 ,
69.Xr rc 8 ,
70.Xr sysctl 8
71.Sh HISTORY
72The
73.Nm
74file appeared in
75.Fx 4.0 .
76.Sh BUGS
77If loadable kernel modules are used to introduce additional kernel
78functionality and sysctls to manage that functionality,
79.Nm
80may be processed too early in the boot process to set those sysctls.
81For example, sysctls to manage the linux emulator cannot be set in
82.Nm
83if the linux emulator is loaded as a module rather than
84compiled into the kernel.
85