Linux下网络流量监控shell脚本

#!/bin/bash
if [ -z "$1" ]
then
    echo "Oops...Please specify network device name."
    echo "Usage:    `basename $0` device"
    echo "eg.     `basename $0` eth0"
    exit 1
else
    dev_name="$1"
fi

/sbin/ifconfig $dev_name 2> /dev/null > /dev/null
if [ $? -ne 0 ]
then
    echo "Oops...Cannot find the specified device."
    exit 1
fi

while true
do
    rece_all1=`/sbin/ifconfig $dev_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`
    send_all1=`/sbin/ifconfig $dev_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`
    sleep 1
    rece_all2=`/sbin/ifconfig $dev_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`
    send_all2=`/sbin/ifconfig $dev_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`
    rece=`expr $rece_all2 - $rece_all1`
    send=`expr $send_all2 - $send_all1`
    clear
    echo "Last second receive:$(($rece/1024)) KB    Last second Send:$(($send/1024)) KB"
    echo "Total receive:$(($rece_all2/1024)) KB ($(($rece_all2/1024/1024))MB)    Total send:$(($send_all2/1024)) KB ($(($send_all2/1024/1024))MB)"
done