Sysctl

sysctl - Kernel-Parameter zur Laufzeit konfigurieren

Beschreibung

• sysctl kann sysctl-Dateien lesen und schreiben
• Procfs erforderlich

Installation

sysctl ist Teil des Pakets procps

Aufruf

sysctl [options] [variable[=value]] [...]
sysctl -p [file or regexp] [...]

Optionen

Unix	GNU	Parameter	Beschreibung
-n	--values		Do not display the key name when printing values
-e	--ignore		Ignore errors about unknown keys
-N	--names		Only display names (maybe useful for programmable completion)
-q	--quiet		Do not display the values set to stdout
-w	--write		Change sysctl settings
-p	--load	[=FILE]	Load in sysctl settings from the file specified or /etc/sysctl.conf if none given Specifying - as filename means reading data from standard input Using this option will mean arguments to sysctl are files, which are read in the order they are specified The file argument may be specified as regular expression
-a	--all		Display all values currently available
	--deprecated		Include deprecated parameters to --all values listing
-b	--binary		Print value without new line
	--system		Load settings from all system configuration files /run/sysctl.d/*.conf /etc/sysctl.d/*.conf /usr/local/lib/sysctl.d/*.conf /usr/lib/sysctl.d/*.conf /lib/sysctl.d/*.conf /etc/sysctl.conf
-r	--pattern pattern		Only apply settings that match pattern. The pattern uses extended regular expression syntax
-A			Alias of -a
-d			Alias of -h
-f			Alias of -p
-X			Alias of -a
-o			Does nothing, exists for BSD compatibility
-x			Does nothing, exists for BSD compatibility
-h	--help		Display help text and exit
-V	--version		Display version information and exit

Parameter

variable

• Name eines Schlüssels, der gelesen werden soll

Beispiel

kernel.ostype

Anstelle eines „.“ kann auch das Trennzeichen „/“ verwendet werden

variable=value

• wird verwendet, um einen Schlüssel in der Form variable=value zu setzen
• wobei variable der Schlüssel und value der Wert ist, auf den er gesetzt werden soll
• Wenn der Wert Anführungszeichen oder Zeichen enthält, die von der Shell analysiert werden, müssen Sie den Wert möglicherweise in doppelte Anführungszeichen setzen
• Dies erfordert die Verwendung des Parameters -w

variable

• is the name of a key to read from
• An example is kernel.ostype. The '/' separator is also accepted in place of a '.'.

variable=value

• is used to set a key, in the form variable=value where variable is the key and 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
• This requires the -w parameter to use

Anwendung

/sbin/sysctl -a

/sbin/sysctl -n kernel.hostname

/sbin/sysctl -w kernel.domainname="example.com"

/sbin/sysctl -p/etc/sysctl.conf

/sbin/sysctl -a --pattern forward

/sbin/sysctl -a --pattern forward$

/sbin/sysctl -a --pattern 'net.ipv4.conf.(eth|wlan)0.arp'

/sbin/sysctl --system --pattern '^net.ipv6'

Konfiguration

Dateien

Datei	Beschreibung
/proc/sys
/etc/sysctl.conf

-p --load [=FILE]

Load in sysctl settings from the file specified or /etc/sysctl.conf if none given

• Specifying - as filename means reading data from standard input
• Using this option will mean arguments to sysctl are files, which are read in the order they are specified
• The file argument may be specified as regular expression

--system

Load settings from all system configuration files

/run/sysctl.d/*.conf
/etc/sysctl.d/*.conf
/usr/local/lib/sysctl.d/*.conf
/usr/lib/sysctl.d/*.conf
/lib/sysctl.d/*.conf
/etc/sysctl.conf

Anhang

Siehe auch

• Sysctl
• Sysctl/Parameter
• Sysctl/Problembehebung

• linux-sysctl-defaults

Dokumentation

Man-Page

• sysctl.conf(5)
• regex(7)

Links

Projekt

1. https://github.com/klaver/sysctl