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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