50.检测网卡状态脚本

1思路：sar -n DEV 1 10监测网卡进出流量，如果进出流量都为0则网卡异常
2#!/bin/bash
3LANG=en#定义语言
4if [ $# -ne 1 ] || ! ip addr show $1 &>/dev/null;then 
5#输入参数是否为1， ! ip addr show判断网卡是否存在
6        echo "Please input correct network card." 
7        exit
8fi
9echo "Checking..."#输出检测信息
10sar_in=`sar -n DEV 1 10 |grep " $1 "|grep -i average:|awk '{print $5}'`
11#进网卡流量
12sar_out=`sar -n DEV 1 10 |grep " $1 "|grep -i average:|awk '{print $6}'`
13#出网卡流量
14if [ "$sar_in" == "0.00" ] && [ "$sar_out" == "0.00" ];then
15#判断进出网卡流量是否都为0
16        while true#while 循环执行判断是否重启网卡
17        do
18             read -p "The network card is down,do you want to restart it?(y or n) " net
19             case $net in
20             y)
21             echo "Restarting..."#输出重启信息
22             ifdown $1 2>/dev/null
23             ifup $1 2>/dev/null
24             if [ $? -eq 0 ];then#判断重启是否成功
25                echo "The network card was restarted successfully!"
26                break#退出循环
27             else
28                echo "DEV $1 failed to start!"
29                break#退出循环
30             fi
31             ;;
32             n)
33             echo "Bye!"
34             exit 1
35             ;;
36             *)
37             echo "Please input y or n."
38             continue#重新循环
39             ;;
40             esac
41        done
42else
43        echo "The network card is in good condition!"
44fi
45使用 ：sh dev_sar.sh eth0