CentOS下如何彻底卸载MySQL？解决卸载不干净的问题

CentOS下如何彻底卸载MySQL？解决卸载不干净的问题

系统：CentOS 6.5，MySQL：MySql 5.6

这里主要解决使用rpm安装的卸载问题，安装方法见：CentOS安装mysql*.rpm提示conflicts with file from package的解决办法

虽说这里的是使用rpm安装的卸载问题，我以为使用yum方式安装的若是遇到相同的问题也同样适用。

查看已经安装的服务

rpm –qa|grep -i mysql

-i 做用是不区分大小写

yum remove mysql mysql-server mysql-libs compat-mysql51
rm -rf /var/lib/mysql
rm /etc/my.cnf
查看是否还有mysql软件：
rpm -qa|grep mysql
有的话继续删除

能够看到有两个安装包

MySQL-server-5.6.19-1.linux_glibc2.5.x86_64.rpm
MySQL-client-5.6.19-1.linux_glibc2.5.x86_64.rpm

删除这两个服务(去掉后缀)

rpm –e MySQL-client-5.6.19-1.linux_glibc2.5.x86_64
rpm -e MySQL-server-5.6.19-1.linux_glibc2.5.x86_64

查看残留的目录：

whereis mysql

而后删除mysql目录：

rm –rf /usr/lib64/mysql

删除相关文件：

rm –rf /usr/my.cnf
rm -rf /root/.mysql_sercret

最关键的：

rm -rf /var/lib/mysql

若是这个目录若是不删除，再从新安装以后，密码仍是以前的密码，不会从新初始化！

网上查了好久都没有文章提到这个，最后仍是本身摸索找出来的。

卸载完成！怎么肯定是否是真的卸载干净了呢？

一是看安装输出：

若是没有卸载干净，安装server时输入只有两行：

[root @localhost opt]# rpm -ivh MySQL-server-5.6.19-1.linux_glibc2.5.x86_64.rpm
Preparing...                ########################################### [100%]
   1:MySQL-server           ########################################### [100%]

卸载干净了安装输入以下：

[root @localhost opt]# rpm -ivh MySQL-server-5.6.19-1.linux_glibc2.5.x86_64.rpm
Preparing...                ########################################### [100%]
   1:MySQL-server           ########################################### [100%]
2014-09-23 07:22:43 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2014-09-23 07:22:43 26041 [Note] InnoDB: Using atomics to ref count buffer pool pages
2014-09-23 07:22:43 26041 [Note] InnoDB: The InnoDB memory heap is disabled
2014-09-23 07:22:43 26041 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2014-09-23 07:22:43 26041 [Note] InnoDB: Compressed tables use zlib 1.2.3
2014-09-23 07:22:43 26041 [Note] InnoDB: Using Linux native AIO
2014-09-23 07:22:43 26041 [Note] InnoDB: Using CPU crc32 instructions
2014-09-23 07:22:43 26041 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2014-09-23 07:22:43 26041 [Note] InnoDB: Completed initialization of buffer pool
2014-09-23 07:22:43 26041 [Note] InnoDB: The first specified data file ./ibdata1 did not exist: a new database to be created!
2014-09-23 07:22:43 26041 [Note] InnoDB: Setting file ./ibdata1 size to 12 MB
2014-09-23 07:22:43 26041 [Note] InnoDB: Database physically writes the file full: wait...
2014-09-23 07:22:43 26041 [Note] InnoDB: Setting log file ./ib_logfile101 size to 48 MB
2014-09-23 07:22:43 26041 [Note] InnoDB: Setting log file ./ib_logfile1 size to 48 MB
2014-09-23 07:22:45 26041 [Note] InnoDB: Renaming log file ./ib_logfile101 to ./ib_logfile0
2014-09-23 07:22:45 26041 [Warning] InnoDB: New log files created, LSN=45781
2014-09-23 07:22:45 26041 [Note] InnoDB: Doublewrite buffer not found: creating new
2014-09-23 07:22:45 26041 [Note] InnoDB: Doublewrite buffer created
2014-09-23 07:22:45 26041 [Note] InnoDB: 128 rollback segment(s) are active.
2014-09-23 07:22:45 26041 [Warning] InnoDB: Creating foreign key constraint system tables.
2014-09-23 07:22:45 26041 [Note] InnoDB: Foreign key constraint system tables created
2014-09-23 07:22:45 26041 [Note] InnoDB: Creating tablespace and datafile system tables.
2014-09-23 07:22:45 26041 [Note] InnoDB: Tablespace and datafile system tables created.
2014-09-23 07:22:45 26041 [Note] InnoDB: Waiting for purge to start
2014-09-23 07:22:45 26041 [Note] InnoDB: 5.6.19 started; log sequence number 0
A random root password has been set. You will find it in '/root/.mysql_secret'.
2014-09-23 07:22:46 26041 [Note] Binlog end
2014-09-23 07:22:46 26041 [Note] InnoDB: FTS optimize thread exiting.
2014-09-23 07:22:46 26041 [Note] InnoDB: Starting shutdown...
2014-09-23 07:22:48 26041 [Note] InnoDB: Shutdown completed; log sequence number 1625977


2014-09-23 07:22:48 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).
2014-09-23 07:22:48 26065 [Note] InnoDB: Using atomics to ref count buffer pool pages
2014-09-23 07:22:48 26065 [Note] InnoDB: The InnoDB memory heap is disabled
2014-09-23 07:22:48 26065 [Note] InnoDB: Mutexes and rw_locks use GCC atomic builtins
2014-09-23 07:22:48 26065 [Note] InnoDB: Compressed tables use zlib 1.2.3
2014-09-23 07:22:48 26065 [Note] InnoDB: Using Linux native AIO
2014-09-23 07:22:48 26065 [Note] InnoDB: Using CPU crc32 instructions
2014-09-23 07:22:48 26065 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2014-09-23 07:22:48 26065 [Note] InnoDB: Completed initialization of buffer pool
2014-09-23 07:22:48 26065 [Note] InnoDB: Highest supported file format is Barracuda.
2014-09-23 07:22:48 26065 [Note] InnoDB: 128 rollback segment(s) are active.
2014-09-23 07:22:48 26065 [Note] InnoDB: Waiting for purge to start
2014-09-23 07:22:48 26065 [Note] InnoDB: 5.6.19 started; log sequence number 1625977
2014-09-23 07:22:48 26065 [Note] Binlog end
2014-09-23 07:22:48 26065 [Note] InnoDB: FTS optimize thread exiting.
2014-09-23 07:22:48 26065 [Note] InnoDB: Starting shutdown...
2014-09-23 07:22:50 26065 [Note] InnoDB: Shutdown completed; log sequence number 1625987




A RANDOM PASSWORD HAS BEEN SET FOR THE MySQL root USER !
You will find that password in '/root/.mysql_secret'.

You must change that password on your first connect,
no other statement but 'SET PASSWORD' will be accepted.
See the manual for the semantics of the 'password expired' flag.

Also, the account for the anonymous user has been removed.

In addition, you can run:

  /usr/bin/mysql_secure_installation

which will also give you the option of removing the test database.
This is strongly recommended for production servers.

See the manual for more instructions.

Please report any problems at http://bugs.mysql.com/

The latest information about MySQL is available on the web at

  http://www.mysql.com

Support MySQL by buying support/licenses at http://shop.mysql.com

New default config file was created as /usr/my.cnf and
will be used by default by the server when you start it.
You may edit this file to change server settings

最后一段中提示了重要信息，不少人由于不喜欢读英文，致使接下来不知道怎么操做！

二就是安装完成，启动服务以后

使用命令：“mysql -uroot -p”输入你以前安装后设置的密码，看能不能登陆，若是还能够登陆，说明没有卸载干净！