linux命令学习-3-sysctl

时间:2021-01-13 14:33:20

sysctl 内核变量配置

Usage:
sysctl [options] [variable[=value] ...]
 
NAME
sysctl - configure kernel parameters at runtime
 
DESCRIPTION
sysctl is used to modify kernel parameters at runtime. The parameters available are those listed under /proc/sys/. Procfs is required for sysctl support
in Linux. You can use sysctl to both read and write sysctl data.
 
Options:
-a, --all display all variables
-A alias of -a
-X alias of -a
--deprecated include deprecated parameters to listing
-b, --binary print value without new line
-e, --ignore ignore unknown variables errors
-N, --names print variable names without values
-n, --values print only values of a variables
-p, --load[=<file>] read values from file
-f alias of -p
--system read values from all system directories
-r, --pattern <expression>
select setting that match expression
-q, --quiet do not echo variable set
-w, --write enable writing a value to variable
-o does nothing
-x does nothing
-d alias of -h
 
-h, --help display this help and exit
-V, --version output version information and exit
  
实例1:
/sbin/sysctl -a
显示所有变量
linux命令学习-3-sysctl
 
实例2:
只打印固定的一个变量
/sbin/sysctl -n kernel.hostname
 
linux命令学习-3-sysctl
 
/sbin/sysctl -n net.ipv4.tcp_timestamps
 
linux命令学习-3-sysctl
 
实例3:
写入内核变量
/sbin/sysctl -w kernel.domainname="example.com"
 
linux命令学习-3-sysctl
 
实例4:
读取数据
/sbin/sysctl -p/etc/sysctl.conf
无输出
 
实例5:
正则匹配
/sbin/sysctl -a --pattern forward
 
linux命令学习-3-sysctl
 
/sbin/sysctl -a --pattern forward$
linux命令学习-3-sysctl
 
 
/sbin/sysctl -a --pattern 'net.ipv4.conf.(eth|wlan)0.arp'
 
linux命令学习-3-sysctl