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HomeDatabaseMysql TutorialCentOS下重置MySQL的root密码的教程_MySQL

本人在CentOS6.4上安装万mysql后,无法通过root进入,因为安装的时候,并没有设置root密码,似乎有个初始随机密码,但是不记得了,太麻烦,直接重置root密码。
首先,你必须要有操作系统的root权限了。要是连系统的root权限都没有的话,先考虑root系统再走下面的步骤。

PS:赋予用于root权限
方法一: 修改 /etc/sudoers 文件,找到%wheel一行,把前面的注释(#)去掉


## Allows people in group wheel to run all commands
%wheel ALL=(ALL) ALL


然后修改用户,使其属于root组(wheel),命令如下:


#usermod -g root tommy


修改完毕,现在可以用tommy帐号登录,然后用命令 sudo su - ,即可获得root权限进行操作。

方法二: 修改 /etc/sudoers 文件,找到root一行,在root下面添加一行,如下所示:


## Allow root to run any commands anywhere
root ALL=(ALL)  ALL
tommy ALL=(ALL)  ALL


修改完毕,现在可以用tommy帐号登录,然后用命令 sudo su - ,即可获得root权限进行操作。

方法三: 修改 /etc/passwd 文件,找到如下行,把用户ID修改为 0 ,如下所示:


tommy:x:500:500:tommy:/home/tommy:/bin/bash


修改后如下


tommy:x:0:500:tommy:/home/tommy:/bin/bash


保存,用tommy账户登录后,直接获取的就是root帐号的权限。


root下类似于安全模式登录系统,有人建议说是pkill mysql,但是我不建议哈。因为当你执行了这个命令后,会导致这样的状况:


/etc/init.d/mysqld status
mysqld dead but subsys locked


这样即使你是在安全模式下启动mysql都未必会有用的,所以一般是这样/etc/init.d/mysqld stop,如果你不幸先用了pkill,那么就start一下再stop咯。
使用rpm包安装完mysql后,按照一下步骤重置root密码:
启动mysql:


#/etc/init.d/mysql start


启动成功后查看mysql进程信息,获取mysqld_safe的安装目录(非常关键):


#ps -ef | grep -i mysql
root  3466  1 0 01:45 pts/1 00:00:00 /bin/sh /usr/bin/mysqld_safe 
--datadir=/var/lib/mysql --pid-file=/var/lib/mysql/BSC.TEST.pid
mysql  3569 3466 16 01:45 pts/1 00:00:00 /usr/sbin/mysqld 
--basedir=/usr 
--datadir=/var/lib/mysql 
--plugin-dir=/usr/lib64/mysql/plugin 
--user=mysql 
--log-error=/var/lib/mysql/BSC.TEST.err 
--pid-file=/var/lib/mysql/BSC.TEST.pid
root  3597 3105 0 01:45 pts/1 00:00:00 grep -i mysql


可以看到mysqld_safe的安装位置(上面标蓝色部分):/usr/bin/
接着执行一下命令停止mysql:


/etc/init.d/mysql stop


以安全方式启动mysql:


#/usr/bin/mysqld_safe --skip-grant-tables >/dev/null 2>&1 &


稍等5秒钟,然后执行以下语句:


#/usr/bin/mysql -u root mysql


注意:mysql与mysql_safe目录一样,都是:/usr/bin/下,这个是通过“ps -ef | grep -i mysql”命令得到的。

出现“mysql>”提示符后输入:


mysql> update user set password = Password('root') where User = 'root';


回车后执行(刷新MySQL系统权限相关的表):


mysql> flush privileges;


再执行exit退出:


mysql> exit;


退出后,使用以下命令登陆mysql,试试是否成功:


#mysql -u root -p


按提示输入密码:


root


但是执行查看数据库命令报错:


mysql> show databases;



ERROR 1820 (HY000): You must SET PASSWORD before executing this statement


解决办法:


mysql> SET PASSWORD=PASSWORD('root');



Query OK, 0 rows affected (0.00 sec)



mysql> flush privileges;



Query OK, 0 rows affected (0.00 sec)



mysql> show databases;



+--------------------+
| Database   |
+--------------------+
| information_schema |
| mysql    |
| performance_schema |
| test    |
+--------------------+
4 rows in set (0.00 sec)


PS:如果在使用mysqladmin的话:


# mysqladmin -u root -p password "test123"



Enter password: 【输入原来的密码】

以上就是CentOS下重置MySQL的root密码的教程_MySQL的内容,更多相关内容请关注PHP中文网(www.php.cn)!


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