1 前言

一个问题，一篇文章，一出故事。
笔者几天前发现Tomcat会因为一个错误而停止服务，虽然进程还在，但是服务已经无任何回应，详细原因如下，

如何修复Tomcat antiJARLocking true警告？

笔者虽然有通知开发处理，但是修改可能有点延迟，于是笔者想给Tomcat写一个服务检查脚本，当异常时自动重启服务。

2 最佳实践

2.1 寻找异常的配置文件

vim ~/scripts/autoTomcatManager.sh

加入如下配置，

#!/bin/bash

tomcatLog="/var/log/tomcat/autoTomcatManager.log"
tomcatUrl="http://localhost:8080"
tomcatKeywords="<title>Apache Tomcat/8.5.81</title>"
tomcatUser="tomcat"
tomcatExt="jsvc"

if [ `curl -s "$tomcatUrl" | grep -i "$tomcatKeywords" | wc -l` = 1 ]; then
        exit
fi
echo `date +"%Y/%m/%d %H:%M:%S"`" Tomcat service failure!" >> "$tomcatLog"
for ((;;)); do
        if [ `pgrep -u "$tomcatUser" "$tomcatExt" | wc -l` = 0 ]; then
                break
        fi
        for i in `pgrep -u "$tomcatUser" "$tomcatExt"`; do
                echo `date +"%Y/%m/%d %H:%M:%S"`" Cleanup Tomcat service!" >> "$tomcatLog"
                kill "$i"
        done
        sleep 1
done
for ((;;)); do
        if [ `systemctl status tomcat.service | grep -i "Active:" | grep -i "Active: active (running)" | wc -l` = 1 ]; then
                break
        fi
        echo `date +"%Y/%m/%d %H:%M:%S"`" Start Tomcat service!" >> "$tomcatLog"
        /usr/bin/systemctl start tomcat.service
        sleep 1
done
exit

2.2 创建服务触发

crontab -e

加入如下配置，

*/5 * * * * sh ~/scripts/autoTomcatManager.sh