docker 检查容器连接数

检测docker 容器的tcp连接情况，并做统计(window 和mac环境不支持)

用法：./detect.sh

detect.sh 源码如下：

#!/usr/bin/env bash

tmp_result="/tmp/docker_connections";

detectTCPConnection(){

    echo "start detecting...";

    list=$(docker ps -f 'status=running' --format "table {{.ID}}");

    list=${list#CONTAINER ID};

    test -z "${list}" && echo "container id is null" && exit 0;

    timestamp=$(date +"%Y%m%d%H%M%S");

    test ! -d "${tmp_result}" && mkdir ${tmp_result};

    cd ${tmp_result};

    for i in $list; do

        pid=$(docker inspect -f {{.State.Pid}} $i);

    echo "start detect for pid:${pid}";

    tmpFile="${i}_${pid}.txt";

    echo  "make file ${tmpFile}";

    test -a "$tmpFile" && rm -f $tmpFile;

    nsenter -t $pid -n netstat |grep ESTABLISHED > $tmpFile;

    echo "end statistic connection for container  ${i}";

    done

}

doStatisticTCPConection(){

    test ! -d "${tmp_result}" && echo "not data for statistic" && exit 0;

    cd ${tmp_result};

    for i in *.txt; do

        echo "${i} tcp connections:$(cat ${i} | grep "6379"  | wc -l)";

    done

}

select i in 'do detect' 'do statistic' 'do both';do

case $i in

'do detect')

detectTCPConnection;

;;

'do statistic')

doStatisticTCPConection;

;;

'do both')

detectTCPConnection;

doStatisticTCPConection;

;;

*)

echo "usage: ./detect.sh ";

;;

esac

done

使用案例：查看每个容器中redis的连接数