使用shell监控网络实时流量

直接上代码：

#!/bin/bash

function usage
{
        echo "Usage: $0 "
        echo "e.g. $0 eth0 2"
        exit 1
}
if [ $# -lt 2 ];then
        usage
fi

eth=$1
interval=$2

in_old=$(cat /proc/net/dev | grep -w $eth | sed -e "s/\(.*\)\:\(.*\)/\2/g" | awk '{ print $1 }' )
out_old=$(cat /proc/net/dev | grep -w $eth | sed -e "s/\(.*\)\:\(.*\)/\2/g" | awk '{ print $9 }' )

while true
do
	sleep ${interval}
	in=$(cat /proc/net/dev | grep -w $eth | sed -e "s/\(.*\)\:\(.*\)/\2/g" | awk '{ print $1 }' )
	out=$(cat /proc/net/dev | grep -w $eth | sed -e "s/\(.*\)\:\(.*\)/\2/g" | awk '{ print $9 }')
	sub_in=$(( ($in-$in_old)/$interval ))
	sub_out=$(( ($out-$out_old)/$interval ))
	echo "Recv rate: $((${sub_in}/1024)) KB/s	Sent rate:  $((${sub_out}/1024)) KB/s "
	in_old=${in}
	out_old=${out}
done
exit 0 

　

输出：

Recv rate: 1175 KB/s Sent rate: 29 KB/s
Recv rate: 1175 KB/s Sent rate: 29 KB/s
Recv rate: 1179 KB/s Sent rate: 31 KB/s
Recv rate: 987 KB/s Sent rate: 33 KB/s
Recv rate: 1159 KB/s Sent rate: 29 KB/s
Recv rate: 1167 KB/s Sent rate: 29 KB/s
Recv rate: 1082 KB/s Sent rate: 27 KB/s
Recv rate: 1085 KB/s Sent rate: 27 KB/s
Recv rate: 1129 KB/s Sent rate: 29 KB/s
Recv rate: 954 KB/s Sent rate: 24 KB/s
Recv rate: 465 KB/s Sent rate: 18 KB/s
Recv rate: 507 KB/s Sent rate: 14 KB/s
Recv rate: 1135 KB/s Sent rate: 30 KB/s

　与dstat的对比：dstat -n -N peth1

1176k 30k
1176k 30k
1180k 31k
987k 33k
1159k 29k
1167k 30k
1083k 27k
1085k 27k
1129k 29k
955k 24k
466k 19k
508k 15k
1135k 30k