监控Linux网络流量的脚本

#!/bin/bash  
if [ -n "$1" ]; then  
eth_name=$1  
else  
eth_name="eth0" 
fi  
i=0 
send_o=`ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`  
recv_o=`ifconfig $eth_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`  
send_n=$send_o  
recv_n=$recv_o  
while [ $i -le 100000 ]; do  
send_l=$send_n  
recv_l=$recv_n  
sleep 1  
send_n=`ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'`  
recv_n=`ifconfig $eth_name | grep bytes | awk '{print $2}' | awk -F : '{print $2}'`  
i=`expr $i + 1`  
send_r=`expr $send_n - $send_l`  
recv_r=`expr $recv_n - $recv_l`  
total_r=`expr $send_r + $recv_r`  
send_ra=`expr \( $send_n - $send_o \) / $i`  
recv_ra=`expr \( $recv_n - $recv_o \) / $i`  
total_ra=`expr $send_ra + $recv_ra`  
sendn=`ifconfig $eth_name | grep bytes | awk -F \( '{print $3}' | awk -F \) '{print $1}'`  
recvn=`ifconfig $eth_name | grep bytes | awk -F \( '{print $2}' | awk -F \) '{print $1}'`  
clear  
echo   "Last second   :    Send rate: $send_r Bytes/sec   Recv rate: $recv_r Bytes/sec   Total rate: $total_r Bytes/sec"  
echo   "Average value:    Send rate: $send_ra Bytes/sec   Recv rate: $recv_ra Bytes/sec   Total rate: $total_ra Bytes/sec"  
echo   "Total traffic after startup:     Send traffic: $sendn   Recv traffic: $recvn"  
done