设置IP地址

#!/bin/bash


#Absolute path to this script
SCRIPT=$(readlink -f $0)
#Absolute path this script is in
SCRIPTPATH=$(dirname $SCRIPT)
echo $SCRIPT
echo $SCRIPTPATH

#Initial defaults
_NAME=ens33
_LOC_IP=192.168.31.91
_GW_IP=192.168.31.1
_PREFIX=24


clear
echo
echo
echo "This script will help you easily set up IP ADDRESS"
echo

#check for root user
if [ "$(id -u)" -ne 0 ] ; then
        echo "You must run this script as root. Sorry!"
        exit 1
fi


#判断IP ADDRESS是否合规
if ! echo $LOC_IP | egrep -q '(^([1-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).)(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){2}([0-9]|[1-9]{2}|1[0-9]{2}|2[0-4][0-9]|25[0-5])$' ; then
        #Read the IP
        read  -p "Please select the IP for this instance: [$_LOC_IP] " LOC_IP
        if ! echo $LOC_IP | egrep -q '(^([1-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).)(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){2}([0-9]|[1-9]{2}|1[0-9]{2}|2[0-4][0-9]|25[0-5])$' ; 
        then
                echo " Selecting default: $_LOC_IP"
                echo
                LOC_IP=$_LOC_IP
        else
                echo " Selecting IP: $LOC_IP"
                echo
        fi
fi


#判断IP GATEWAY是否合规
if ! echo $GW_IP | egrep -q '(^([1-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).)(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){2}([0-9]|[1-9]{2}|1[0-9]{2}|2[0-4][0-9]|25[0-5])$' ; then
        #Read the IP
        read  -p "Please select the IP GW for this instance: [$_GW_IP] " GW_IP
        if ! echo $GW_IP | egrep -q '(^([1-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).)(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5]).){2}([0-9]|[1-9]{2}|1[0-9]{2}|2[0-4][0-9]|25[0-5])$' ; 
        then
                echo " Selecting default: $_GW_IP"
                echo
                GW_IP=$_GW_IP
        else
                echo " Selecting GW: $GW_IP"
                echo
        fi
fi

cat>/etc/sysconfig/network-scripts/ifcfg-$_NAME<<EOF
TYPE="Ethernet"
BOOTPROTO="static"
ONBOOT="yes"
DEVICE="$_NAME"
NETMASK=$_PREFIX
GATEWAY=$GW_IP
IPADDR=$LOC_IP
DNS1=114.114.114.114
EOF
systemctl restart network
ifconfig