统计网卡流量的两段shell脚本(使用ifconfig)

使用shell脚本计算Linux网卡流量，方法中最关键点：

ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print $2}'

通过ifconfig eth0|grep bytes 得到输入输出的流量。

/@rac2=>dd2$ifconfig eth0|grep bytes 
RX bytes:1638005313300 (1.4 TiB) TX bytes:3408060482049 (3.0 TiB)

再将结果通过awk 得出所要的字段值。
固定时间得到这些值，在写个循环计算一下就能得到网卡流量。
完整代码：

代码一：

#!/bin/bash
# 统计网卡流量
# link：www.jb51.net
# date：2013/2/26
n=10

date
rm -rf /tmp/ifconfig_log
while (( $n >= 0  ))
do
  n=$(($n - 1));
  date >> /tmp/ifconfig_log
  ifconfig eth1 >> /tmp/ifconfig_log
  sleep 1
done

grep "RX bytes:" /tmp/ifconfig_log | awk -F"[:| ]" '{print $13}' | awk 'BEGIN{tmp=$1}{if(FNR > 1)print $1-tmp}{tmp=$1}'

代码二：

#!/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 "==================================================" 
  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"
  echo "=================================================="
done