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与很多软件安装一样,如果是第二次安装,比第一次安装要纠结得多,很多东西可能因为没有删除干净,会安装不上,我这次安装mysql就是一个例子。
下面是怎样删除干净的方法:
1. rpm删除
先用rpm –qa |grep mysql查看安装的rpm包
再用(注意只能是client在前)
rpm -e MySQL-client-community-5.1.40-0.rhel5
rpm -e MySQL-server-community-5.1.40-0.rhel5
两个命令删除服务器端和客户端。
2. 删除老版本的开发头文件和库
这里可以肯定的是随着上面两个rpm包的删除,/usr/bin/下相应的很多mysql打头的文件和/usr/share/下的mysql文件夹都会删除,但是还有一些默认不会删除的如下:
/var/lib下面是否有一个mysql文件夹,这里是老版本的开发库。
/etc/下面是否有my.cnf文件,是老版本的配置文件。
用rm命令将以上文件全部删除。
3. 删除可能还在运行的mysql进程——这是最容易忽略的地方
可以用ps –ef | grep mysql查看下
-bash-3.1# ps -ef |grep mysql
root 4885 1 0 10:43 ? 00:00:00 /bin/sh bin/mysqld_safe --user=mysql
mysql 4984 4885 0 10:43 ?00:00:00 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --user=mysql --log-error=/usr/local/mysql/data/namenode.err --pid-file=/usr/local/mysql/data/namenode.pid --socket=/tmp/mysql.sock --port=3306
root 8116 7066 0 21:11 pts/1 00:00:00 grep mysql
多于一个时把他们全部kill掉。
否则会在你安装server的rpm包的时候报启动错误,我的报错最后两行如下:
Starting MySQL..Manager of pid-file quit without updating file.[失败]
Giving mysqld 2 seconds to start.
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