监控网卡的实时流量信息

[root@dns shell]# cat network.sh
#!/bin/bash
   
    
ETH=$1
ETH=${ETH:-eth1}
IP=`ifconfig $ETH|awk -F '[ :]+' '/inet addr/{print $4}'`
    
while true;do
        let I+=1
        NOW=`date +"%F %T"`
        TX1=`ifconfig $ETH|grep bytes|awk -F '[ :]+' '{print $9}'`
        RX1=`ifconfig $ETH|grep bytes|awk -F '[ :]+' '{print $4}'`
        sleep 1
        TX2=`ifconfig $ETH|grep bytes|awk -F '[ :]+' '{print $9}'`
        RX2=`ifconfig $ETH|grep bytes|awk -F '[ :]+' '{print $4}'`
    
        let TX=(TX2-TX1)/1024
        let RX=(RX2-RX1)/1024
        let TX_TOTAL+=$TX
        let RX_TOTAL+=$RX
        let TX_AVERAGE=TX_TOTAL/${I}
        let RX_AVERAGE=RX_TOTAL/${I}
    
        clear
    
        printf "%10s\t%20s\n" "Device $ETH [$IP]" "$NOW"
        echo "============================================================="
        printf "%10s\t%20s\t%20s\n" CURRENT: in:${RX}KB/s out:${TX}KB/s
        printf "%10s\t%20s\t%20s\n" AVERAGE: in:${RX_AVERAGE}KB/s out:${TX_AVERAGE}KB/s
        printf "%10s\t%20s\t%20s\n" TOTAL: in:${RX_TOTAL}KB out:${TX_TOTAL}KB
done