1.\" Copyright (c) 1999 Chris Costello <chris@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd June 30, 2022 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 40file is 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/rc.d/sysctl_lastload -compact 56.It Pa /etc/rc.d/sysctl 57.Xr rc 8 58script which processes 59.Nm 60early on in the process of transitioning to multi-user mode. 61.It Pa /etc/rc.d/sysctl_lastload 62.Xr rc 8 63script which processes 64.Nm 65shortly before the system reaches the multi-user mode. 66.It Pa /etc/sysctl.conf 67Initial settings for 68.Xr sysctl 8 . 69.It Pa /etc/sysctl.conf.local 70Machine-specific settings for sites with a common 71.Pa /etc/sysctl.conf . 72.El 73.Sh EXAMPLES 74To turn off logging of programs that exit due to fatal signals you may use 75a configuration like 76.Bd -literal -offset indent 77# Configure logging. 78kern.logsigexit=0 # Do not log fatal signal exits (e.g., sig 11) 79.Ed 80.Sh SEE ALSO 81.Xr rc.conf 5 , 82.Xr rc 8 , 83.Xr sysctl 8 84.Sh HISTORY 85The 86.Nm 87file appeared in 88.Fx 4.0 . 89.Sh BUGS 90If loadable kernel modules are used to introduce additional kernel 91functionality and sysctls to manage that functionality, 92.Nm 93may be processed too early in the boot process to set those sysctls. 94Please consult 95.Xr rcorder 8 96to learn more about the ordering of 97.Xr rc 8 98scripts. 99