脚本的功能:
首先,检测mysql端口是否正常存在,端口不存在就执行启动mysql服务,当然,启动的脚本的位置根据你的安装路径会有不同,然后如果端口存在,则有mysql服务在运行,那么检测mysql状态,能不能正常连接,如能正常连接说明mysql正常,不做任何处理,如果不能正常连接,则杀掉所有mysql进程,然后启动mysql服务,为什么要杀掉进程而不进行正常的重起呢,是因为有时候mysql是不能正常关闭的,所以不能正常重起,所以保险的做法是杀掉进程,然后启动服务。
#!/bin/bash
/usr/bin/nmap localhost |grep 3306
if [ $? -eq 0 ]
then
/usr/local/mysql/bin/mysql -uxxxxx -pxxxxxx --connect_timeout=5 -e "show databases;"
if [ $? -ne 0 ]
then
/bin/ps aux |grep mysql |grep -v grep | awk ’{print $2}’ | xargs kill -9
/usr/local/mysql/bin/mysqld_safe --user=mysql & > /dev/null
fi
else
/usr/local/mysql/bin/mysqld_safe --user=mysql & > /dev/null
fi

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