shell 常用脚本维护笔记

Centos7.5 IP地址维护

#!/usr/bin/bash
IPADDR=$(ifconfig|grep inet|sed '2,$d'|awk '{print $2}')
GATEWAY=$(ifconfig|grep inet|sed '2,$d'|awk '{print $2}'|awk -F "." '{print $1"."$2"."$3".1"}')
NETMASK=$(ifconfig|grep inet|sed '2,$d'|awk '{print $4}')
DNS1=$GATEWAY
DNS2=8.8.8.8

sed 's/dhcp/static/' /etc/sysconfig/network-scripts/ifcfg-eth0 > /etc/sysconfig/network-scripts/ifcfg-eth0.bk
if [ $? -eq 0 ]; then

        cat >> /etc/sysconfig/network-scripts/ifcfg-eth0.bk << EOF
        IPADDR=$IPADDR
        GATEWAY=$GATEWAY
        NETMASK=$NETMASK
        DNS1=$DNS1
        DNS2=$DNS2
        EOF
else
        echo "sed err"
fi