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Diffstat (limited to 'man/sysctl.8')
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diff --git a/man/sysctl.8 b/man/sysctl.8 new file mode 100644 index 0000000..fe555bd --- /dev/null +++ b/man/sysctl.8 @@ -0,0 +1,196 @@ +.\" +.\" Copyright (c) 2011-2023 Craig Small <csmall@dropbear.xyz> +.\" Copyright (c) 2013-2023 Jim Warner <james.warner@comcast.net> +.\" Copyright (c) 2011-2012 Sami Kerola <kerolasa@iki.fi> +.\" Copyright (c) 2004-2006 Albert Cahalan +.\" Copyright (c) 1999 George Staikos <staikos@0wned.org> +.\" +.\" This program is free software; you can redistribute it and/or modify +.\" it under the terms of the GNU General Public License as published by +.\" the Free Software Foundation; either version 2 of the License, or +.\" (at your option) any later version. +.\" +.\" +.TH SYSCTL "8" "2023-08-19" "procps-ng" "System Administration" +.SH NAME +sysctl \- configure kernel parameters at runtime +.SH SYNOPSIS +.B sysctl +[\fIoptions\fR] [\fIvariable\fR[\fB=\fIvalue\fR]] [...] +.br +.B sysctl \-p +[\fIfile\fR or \fIregexp\fR] [...] +.SH DESCRIPTION +.B sysctl +is used to modify kernel parameters at runtime. The parameters available +are those listed under \fI/proc/sys/\fR. Procfs is required for +.B sysctl +support in Linux. You can use +.B sysctl +to both read and write sysctl data. +.SH PARAMETERS +.TP +.I variable +The name of a key to read from. An example is kernel.ostype. The '/' +separator is also accepted in place of a '.'. +.TP +.IR variable = value +To set a key, use the form +.IR variable = value +where +.I variable +is the key and +.I value +is the value to set it to. If the value contains quotes or characters +which are parsed by the shell, you may need to enclose the value in double +quotes. +.TP +\fB\-n\fR, \fB\-\-values\fR +Use this option to disable printing of the key name when printing values. +.TP +\fB\-e\fR, \fB\-\-ignore\fR +Use this option to ignore errors about unknown keys. +.TP +\fB\-N\fR, \fB\-\-names\fR +Use this option to only print the names. It may be useful with shells that +have programmable completion. +.TP +\fB\-q\fR, \fB\-\-quiet\fR +Use this option to not display the values set to stdout. +.TP +\fB\-w\fR, \fB\-\-write\fR +Force all arguments to be write arguments and print an error if +they cannot be parsed this way. +.TP +\fB\-p\fR[\fIFILE\fR], \fB\-\-load\fR[=\fIFILE\fR] +Load in \fBsysctl\fR settings from the file specified or \fI/etc/sysctl.conf\fR +if none given. Specifying \- as filename means reading data from standard +input. Using this option will mean arguments to +.B sysctl +are files, which are read in the order they are specified. +The file argument may be specified as regular expression. +.TP +\fB\-a\fR, \fB\-\-all\fR +Display all values currently available. +.TP +\fB\-\-deprecated\fR +Include deprecated parameters to +.B \-\-all +values listing. +.TP +\fB\-b\fR, \fB\-\-binary\fR +Print value without new line. +.TP +\fB\-\-system\fR +Load settings from all system configuration files. See the +.B SYSTEM FILE PRECEDENCE +section below. +.TP +\fB\-r\fR, \fB\-\-pattern\fR \fIpattern\fR +Only apply settings that match +.IR pattern . +The +.I pattern +uses extended regular expression syntax. +.TP +\fB\-A\fR +Alias of \fB\-a\fR +.TP +\fB\-d\fR +Alias of \fB\-h\fR +.TP +\fB\-f\fR +Alias of \fB\-p\fR +.TP +\fB\-X\fR +Alias of \fB\-a\fR +.TP +\fB\-o\fR +Does nothing, exists for BSD compatibility. +.TP +\fB\-x\fR +Does nothing, exists for BSD compatibility. +.TP +\fB\-h\fR, \fB\-\-help\fR +Display help text and exit. +.TP +\fB\-V\fR, \fB\-\-version\fR +Display version information and exit. +.SH SYSTEM FILE PRECEDENCE +When using the \fB\-\-system\fR option, +.B sysctl +will read files from directories in the following list in given +order from top to bottom. Once a file of a given filename is loaded, any +file of the same name in subsequent directories is ignored. + +/etc/sysctl.d/*.conf +.br +/run/sysctl.d/*.conf +.br +/usr/local/lib/sysctl.d/*.conf +.br +/usr/lib/sysctl.d/*.conf +.br +/lib/sysctl.d/*.conf +.br +/etc/sysctl.conf + +All configuration files are sorted in lexicographic order, regardless of the +directory they reside in. Configuration files can either be completely +replaced (by having a new configuration file with the same name in a +directory of higher priority) or partially replaced (by having a configuration +file that is ordered later). +.SH EXAMPLES +/sbin/sysctl \-a +.br +/sbin/sysctl \-n kernel.hostname +.br +/sbin/sysctl \-w kernel.domainname="example.com" +.br +/sbin/sysctl \-p/etc/sysctl.conf +.br +/sbin/sysctl \-a \-\-pattern forward +.br +/sbin/sysctl \-a \-\-pattern forward$ +.br +/sbin/sysctl \-a \-\-pattern 'net.ipv4.conf.(eth|wlan)0.arp' +.br +/sbin/sysctl \-\-pattern '\[char94]net.ipv6' \-\-system +.SH DEPRECATED PARAMETERS +The +.B base_reachable_time +and +.B retrans_time +are deprecated. The +.B sysctl +command does not allow changing values of these +parameters. Users who insist to use deprecated kernel interfaces should push values +to \fB/proc\fR file system by other means. For example: +.PP +echo 256 > /proc/sys/net/ipv6/neigh/eth0/base_reachable_time +.SH FILES +.I /proc/sys +.br +.I /etc/sysctl.d/*.conf +.br +.I /run/sysctl.d/*.conf +.br +.I /usr/local/lib/sysctl.d/*.conf +.br +.I /usr/lib/sysctl.d/*.conf +.br +.I /lib/sysctl.d/*.conf +.br +.I /etc/sysctl.conf +.SH SEE ALSO +.BR proc (5), +.BR sysctl.conf (5), +.BR regex (7) +.SH AUTHOR +.UR staikos@0wned.org +George Staikos +.UE +.SH "REPORTING BUGS" +Please send bug reports to +.UR procps@freelists.org +.UE |