linux centos7 修改默认网卡命名规则为eth0脚本

CentOS6之前基于传统的命名方式如：eth1，eth0....
Centos7提供了不同的命名规则，默认是基于固件、拓扑、位置信息来分配。这样做的优点是命名是全自动的、可预知的，缺点是比eth0、wlan0更难读。比如enp5s0

系统环境

[root@demo1 ~]# cat /etc/redhat-release 
CentOS Linux release 7.6.1810 (Core) 
[root@demo1 ~]# uname -a
Linux demo1 3.10.0-957.21.3.el7.x86_64 #1 SMP Tue Jun 18 16:35:19 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
[root@demo1 ~]# date
2021年 07月 01日 星期四 14:28:21 CST

脚本使用

等待60秒进行重启即可，60秒内随时按下Ctrl+C取消重启

重启后网卡名称已设置为eth0

配置恢复

执行恢复操作后会恢复至之前的ens命名规则

有部分机器恢复后会出现还是eth0的情况，可以使用nmtui进行修改下即可

脚本代码

#!/bin/bash
PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:~/bin
export PATH

cp="/bin/cp"
mv="/bin/mv"
BAK_PATH="/usr/src"
#GRUB_FILE="/etc/sysconfig/grub"
GRUB_FILE2="/etc/default/grub"
GRUB_CFG="/boot/grub2/grub.cfg"
DATE_NEW=`date +"%y-%m-%d"`
FILE_PATH="/etc/sysconfig/network-scripts"
FILE_NAMES=`ls ${FILE_PATH} | grep ifcfg | grep -Ev 'bak|lo'`
IPADDR=`ifconfig | grep -E '^ens' -A 1 | tail -1 | awk -F'[ ]+' '{print $3}'`

CHECK_ROOT() {
        [[ $EUID != 0 ]] && echo -e "${ERROR} 当前账号非ROOT(或没有ROOT权限)，无法继续操作，请使用${GREEN_BACKGROUND_PREFIX} sudo su ${FONT_COLOR_SUFFIX}来获取临时ROOT权限（执行后会提示输入当前账号的密码）。" && exit 1
}

CHKECK_IP () {
        CHECK_STEP1=`echo $1 | awk -F"." '{print NF}'`
        if [ $CHECK_STEP1 -eq 4 ] || [ $CHECK_STEP1 -eq 6 ]
        then
                CHECK_STEP2=`echo $1 | awk -F"." '{if ($1!=0 && $NF!=0) split ($0,IPNUM,".")} END \
        { for (k in IPNUM) if (IPNUM[k]==0) print IPNUM[k]; else if (IPNUM[k]!=0 && IPNUM[k]!~/[a-z|A-Z]/ && length(IPNUM[k])<=3 &&
IPNUM[k]<255 && IPNUM[k]!~/^0/) print IPNUM[k]}'| wc -l`
                if [ $CHECK_STEP2 -eq $CHECK_STEP1 ]
                then
                        echo 0
                else
                        echo 1
                fi
        else
                echo 1
        fi
}

RollBACK() {
    cp $BAK_PATH/grub2.${DATE_NEW} $GRUB_FILE2
    BAK_NETWORK=`ls -lrth $BAK_PATH | grep ifcfg | tail -1 | awk '{print $NF}'`
    NEW_NETWORK=`ls -lrth $BAK_PATH | awk '/ifcfg-ens/{print $NF}' | awk -F'.' '{print $1}' | tail -1`
    cp $BAK_PATH/$BAK_NETWORK $FILE_PATH/$NEW_NETWORK
    mv -bf $FILE_PATH/ifcfg-eth0 /tmp >/dev/null 2>&1
    echo "Script done!"
}

echo "是否修改以下网卡配置文件: 
$FILE_NAMES
"
echo && stty erase '^H' && read -p "continue?(y继续/b还原/*退出): " YN
case $YN in
y)
    CHECK_ROOT
    CHECK_IPADDR=`CHKECK_IP $IPADDR`
    if [ $CHECK_IPADDR -eq 1 ]
    then
         echo "这个 $IPADDR 不是正确合法的有效IP !"
         exit 110
    fi
    for NAME in $FILE_NAMES; do
        PD=`grep "" $FILE_PATH/$NAME | wc -l`
        if [[ $PD -eq 0 ]]; then
            continue
        fi
        DEVN=`grep "NAME" $FILE_PATH/$NAME | awk -F'=' '{print $2}'`
        cp $FILE_PATH/$NAME $BAK_PATH/${NAME}.${DATE_NEW}
        #cp $GRUB_FILE $BAK_PATH/grub.${DATE_NEW}
        cp $GRUB_FILE2 $BAK_PATH/grub2.${DATE_NEW}
        trap 'onCtrlC' INT
        function onCtrlC () {
        echo '检测到用户按下Ctrl+C尝试终止脚本,正在进行回滚...'
        RollBACK
        exit 110
        }
        sed -i "s/$DEVN/eth0/g" $FILE_PATH/$NAME
        sed -i "/UUID/d" $FILE_PATH/$NAME
        mv $FILE_PATH/$NAME $FILE_PATH/ifcfg-eth0
        #sed -i '/rhgb quiet/s/.$//' $GRUB_FILE
        #sed -i '/rhgb quiet/s/$/ net.ifnames=0 biosdevname=0 /' $GRUB_FILE
        #sed -i '/rhgb quiet/s/.$/\"/' $GRUB_FILE
        sed -i '/rhgb quiet/s/.$//' $GRUB_FILE2
        sed -i '/rhgb quiet/s/$/ net.ifnames=0 biosdevname=0 /' $GRUB_FILE2
        sed -i '/rhgb quiet/s/.$/\"/' $GRUB_FILE2

        echo ""
        echo && stty erase '^H' && read -p  "重新生成GRUB...(y/n): " NG
case $NG in
y)
    grub2-mkconfig -o $GRUB_CFG
    echo "正在准备重启..."
    IFNAMES=`grep "ifnames" $GRUB_CFG | wc -l`
    if [[ ! $IFNAMES -ge 2 ]]; then echo "$GRUB_CFG 异常,请手动检查,正在进行回滚..." ; RollBACK ; grub2-mkconfig -o $GRUB_CFG; exit 110; fi
    shutdown -r 1
    trap 'onCtrlC' INT
    function onCtrlC () {
    echo '检测到用户按下Ctrl+C尝试终止脚本,正在取消重启...'
    shutdown -c
    exit 110
    }
    for ((s=59;s>0;s--))
    do
        [ $s -gt 0 -a $s -lt 10 ] && echo "距离关机还有 0$s 秒" || echo "距离关机还有 $s 秒"
        sleep 1
        clear
    done
;;
*)
    echo "Input Error! "
    echo "Script Exit... "
    exit 110
;;
esac
    done
;;
b)
    RollBACK
    grub2-mkconfig -o $GRUB_CFG
    exit 110
;;
*)
    exit 110
;;
esac