一个检查 nginx 服务是否正在运行的 shell 脚本，带有操作

Question

#!/bin/bash
date=$(date +"%Y-%m-%d %H:%M:%S")
getpid=$(pgrep nginx | wc -l 
if [ "$getpid" > 0 ]
then
  echo 'Nginx is Fine, It is Running at' $date
else
  echo "Error on Nginx and stoped at" $date
  sudo fuser -k 443/tcp
  sudo service nginx start
  sudo service  monit start
  sudo monit monitor all
  echo "Error on Nginx and stoped at" $date | mailx -s "The Nginx Stop - But it is Fixed" -A /root/nginx_log3.txt mymail.com
fi
exit 0;

我看到了几种检查服务的方法：

$(ps ax | grep myName | fgrep -v grep | awk '{ print $1 }')

或

if (( $(ps -ef | grep -v grep | grep $service | wc -l) > 0 ))

还有几种方法...

检查进程是否正在运行的无数方法，但问题是，即使我终止nginx，任何使用 PS 的命令总是会带来许多带有pid 值的结果！因为pgrep 在我停止服务 nginx 后总是显示 0，而gprep 似乎很适合与小于任何 pid 的值 0 进行比较，

因为如果它已经运行，总是显示 pid 高于 velor 0，pgrep 是路径，但问题是我有一个 crontab 每 3 分钟运行一次这个脚本，即使进程正在运行， pid大于零，正在重启服务！

我发现几个博客教授了几个脚本，但没有一个有效！

我有monit 来保持服务活动，但有时它会失败。

显然，我不确定如何将提取的 pid 的值与值 0 进行比较：

getpid=$(pgrep nginx | wc -l)
    if [ "$getpid" > 0 ]

因为服务总是每 3 分钟重启一次，即使服务以 pid 运行（值大于 0）运行也是如此

非常感谢您的帮助！

Answer 1

我可能会检查您尝试提供的 www 服务，而不是该服务是否正在运行。看看这些不同的例子：

    https=$(nc -z localhost 443)
    http=$(nc -z localhost 80)
    netstt_cnt=$(netstat -ntlp | grep httpd | wc -l)

    http_issues=""
    if [[ ! $https ]] || [[ ! $http ]] ;then
        http_issues=" -Http/https ports not detected "
    fi
    if [ $netstt_cnt -ne 2 ] ;then
        http_issues="${http_issues} -Netstat not reporting httpd "
    fi

    # -- if http_host_check is set perform httpd checks
    local code_stat=""
    if [[ $http_host_check ]] ;then
        http_code=$(curl --write-out %{http_code} --silent --output /dev/null $http_host_check)
        if [ $http_code -lt 1 ] ;then
            http_issues="${http_issues} -Apache NOT serving pages http_code=$http_code. "
        elif [ $http_code -gt 399 ] ;then
            http_issues="${http_issues} -Apache Error http_code=$http_code on test page ${http_host_check}. "
        fi
        code_stat=", (http_code=${http_code}) "
    fi

    # -- php FPM sock, see readonly var $PHP_FPM_SOCK for use set to "" to disable this check.
    if [[ $PHP_FPM_SOCK ]] ;then
        if ! echo /dev/null | socat UNIX:${PHP_FPM_SOCK} - ;then
            http_issues="${http_issues} -php-fpm sock not communicating"
        fi
    fi

    if [[ $http_issues ]] ;then
            echo "Error on Nginx and stoped at" $date
            sudo service nginx stop
            sudo service  monit stop
            sudo fuser -k 443/tcp
            sleep 10    
            sudo service nginx start
            sudo service  monit start
            sudo monit monitor all
            if [[ $http_host_check ]] ;then
                http_code=$(curl --write-out %{http_code} --silent --output /dev/null $http_host_check)
             if [ $http_code -lt 1 ] ;then
                http_issues="${http_issues} -Apache NOT serving pages http_code=$http_code. "
            elif [ $http_code -gt 399 ] ;then
                http_issues="${http_issues} -Apache Error http_code=$http_code on test page ${http_host_check}. "
            fi
            sleep 5
            code_stat=", (http_code=${http_code}) "
            echo "Webserver had a problem, current status is $code_stat" $date | mailx -s "The Nginx stop: $code_stat" -A /root/nginx_log3.txt mymail.com  
    fi

    echo "Current Status : $http_issues"

更新：这里添加了超级简单的示例：

http_code=$(curl --write-out %{http_code} --silent --output /dev/null http://my_domain.com/)
    if [ $http_code -lt 1 ] ;then
        echo "${http_issues} -Apache NOT serving pages http_code=$http_code. "
        // ... do something here (restart web server)..
    fi