需求是我们需要对服务器上的流量进行监控，网络上有个流传的check_traffic.sh，它需要被监控机开启snmp。但是感觉都使用上了nagios还要开snmp。。。有点斧子剪刀一起用的感觉，所以就动手写了个监控流量的shell：

#!/bin/shusage() { echo "Usage: $0 [-n <eth0>] [-w <tx rx>] [-c <tx rx>]" 1>&2; exit 1; }foundw=0;foundc=0;foundn=0;for item in $@ ; do    if [[ $foundn == 1 ]]; then        n=$item;        foundn=2;        continue;    fi    if [[ $foundw == 1 ]]; then        w1=$item;        foundw=2;        continue;    fi    if [[ $foundw == 2 ]]; then        w2=$item;        foundw=3;        continue;    fi    if [[ $foundc == 1 ]]; then        c1=$item;        foundc=2;        continue;    fi    if [[ $foundc == 2 ]]; then        c2=$item;        foundc=2;        continue;    fi    if [[ "$item" == "-w" ]]; then        foundw=1;        continue;    fi    if [[ "$item" == "-c" ]]; then        foundc=1;        continue;    fi    if [[ "$item" == "-n" ]]; then        foundn=1;        continue;    fidoneif [ -z "${w1}" ] || [ -z "${w2}" ] || [ -z "${c1}" ] || [ -z "${c2}" ] || [ -z "${n}" ]; then    usagefiR1=`cat /sys/class/net/$n/statistics/rx_bytes`T1=`cat /sys/class/net/$n/statistics/tx_bytes`sleep 1R2=`cat /sys/class/net/$n/statistics/rx_bytes`T2=`cat /sys/class/net/$n/statistics/tx_bytes`TBPS=`expr $T2 - $T1`RBPS=`expr $R2 - $R1`TMBPS=`expr $TBPS / 1024 / 128`RMBPS=`expr $RBPS / 1024 / 128`if [[ $TMBPS -ge $c1 ]] || [[ $RMBPS -ge $c2 ]] ; then    echo "Critical - current is ${TMBPS}, ${RMBPS}";    exit 2;fiif [[ $TMBPS -ge $w1 ]] || [[ $RMBPS -ge $w2 ]] ; then    echo "WARNING - current is ${TMBPS}, ${RMBPS}";    exit 1;fiecho "OK - current is ${TMBPS}, ${RMBPS}";exit 0;

其中的w和c的数值单位都是Mb。

nagios监控流量脚本