mysql启动异常mysql.sock 启动mysql错误解决方法,学会查看错误日志:mysql.sock丢失,mysqld_safe启动报错 转载自:http://www.cnblogs.com/super-lucky/p/superlucky.html 本人还是个菜鸟,下面是我的经验之谈,能解决一些问题,有不对的地方,敬请斧正。
mysql启动异常mysql.sock启动mysql错误解决方法,学会查看错误日志:mysql.sock丢失,mysqld_safe启动报错
转载自:http://www.cnblogs.com/super-lucky/p/superlucky.html
本人还是个菜鸟,下面是我的经验之谈,能解决一些问题,有不对的地方,敬请斧正。
我的是CentOS6.3+MySQL5.1.57。
重启了一次服务器后,使用> mysql -u root -p登陆是出现下面的错误:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
于是,我检察mysql状态:
? ? ? ?>?/etc/rc.d/init.d/mysqld ?status ?
? ? ? ? ? 显示stop,未运行。
? ? ? ?>/etc/rc.d/init.d/mysqld ?restart
? ? ? ? ?Stopping mysqld: [ OK ]
? ? ? ? ?MySQL Daemon failed to start.
? ? ? ? ?Starting mysqld: [ FAILED]
? ? ? ?>ps -ef | grep mysql
? ? ? ? ?root 28221 27474 0 14:18 pts/0 00:00:00 grep mysql ? 只有这一条
至此,我可以确定,mysql无法启动。
我开始排错,首先发现/tmp/mysql.sock不存在
? ? ? ? >vim /etc/my.cnf
? ? ? ? ??socket=/var/lib/mysql/mysql .sock
? ? ? ? ??/var/lib/mysql/mysql .sock同样不存在
? ? ? ? >find / -name mysql.sock
? ? ? ? ? 显示为空,未查询到mysql.sock文件,mysql.sock文件丢失了。
我看网上有人说mysql.sock套接字文件可以简单地通过重启服务器重新创建得到它,
? ? ? ? ?>init 6 ? ? ?重启命令
? ? ? ? ? ?重启后发现错误还是那样,没有任何改变,mysql.sock重启服务器未自动生成。
接下来了解到mysql.sock是一个临时文件,在mysql启动时会自动生成,我的服务器未启动,自然就没有mysql.sock文件。
我尝试安全启动模式,mysqld_safe试图通过工作目录找到服务器和数据库,但mysqld_safe还是失败。
? ? ? ?>mysqld_safe &
? ? ? ? ?Starting mysqld daemon with databases from ....../mysql/var?
? ? ? ? ?STOPPING server from pid file ??.......pid
? ? ? ? ?130802 15:17:11 mysqld ended
各种命令尝试无效的情况下,我开始了本次最大的收获----学会看错误日志。
在错误日志中,启动失败的原因极为明显,file ‘./mysql-bin。000004’ not found,failed to open!
?mysql开启了bin日志功能,到数据库根目录查看该文件是存在的,可能是文件权限的问题。
? ? ? ?>chown -R mysql:mysql /....../mysql/var
? ? ? ?>mysqld_safe &
? ? ? ?>/etc/rc.d/init.d/mysqld ?restart
? ? ? ? ?Stopping mysqld: [ OK ]
? ? ? ? ?Starting mysqld: [?OK]
? ?成功启动了!~
? 此时mysql.sock文件出现了,在/var/lib/mysql/mysql .sock。如下图所示,以”s”开头的文件都是socket文件。
? ? ? ? ? > mysql -u root -p
? ? ? ? ? ? ?ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
/tmp/mysql.sock
? ? ? ? ? 解决这个错误很简单,因为/tmp/mysql.sock不存在,用这样的方法:
? ? ? ? ? >ln -s /var/lib/mysql/mysql .sock ? /tmp/mysql .sock
以”l”开头的文件是软链接文件。或者可以通过修改/etc/my.cnf文件来修正它。
? ?成功解决了!~
就是这样一个问题折腾了我这么久,错误日志让它无所遁形。查看错误日志可以明确问题所在,而不是像我之前那样盲目的找错。
俗话说授人以鱼不如授人以渔,学会查看日志,你也可以方便快捷的解决问题了。
错误使人进步,我与这个错误斗争了四个多小时,对linux的“一切皆文件”这句话有了更深的了解,对我学习文件系统管理(目录树)有很大的帮助,让我的思维真正的从windows操作系统转向成linux系统。并最终解决问题,很有成就感,我喜欢这种感觉。
希望能对阅读的你有所帮助,谢谢!~
?

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