linux下mysql的root密码忘记----解决方案

1．首先确认服务器出于安全的状态，也就是没有人能够任意地连接MySQL数据库。 
          因为在重新设置MySQL的root密码的期间，MySQL数据库完全出于没有密码保护的 
    状态下，其他的用户也可以任意地登录和修改MySQL的信息。可以采用将MySQL对 
    外的端口封闭，并且停止Apache以及所有的用户进程的方法实现服务器的准安全 
    状态。最安全的状态是到服务器的Console上面操作，并且拔掉网线。

2．修改MySQL的登录设置： 
# vi /etc/my.cnf 
在[mysqld]的段中加上一句：skip-grant-tables 
例如： 
[mysqld] 
datadir=/var/lib/mysql 
socket=/var/lib/mysql/mysql.sock 
skip-grant-tables 
保存并且退出vi。

3．重新启动mysqld 
# /etc/init.d/mysqld restart 
Stopping MySQL: [ OK ] 
Starting MySQL: [ OK ]

4．登录并修改MySQL的root密码 
# /usr/bin/mysql 
Welcome to the MySQL monitor. Commands end with ; or \g. 
Your MySQL connection id is 3 to server version: 3.23.56 
Type 'help;' or '\h' for help. Type '\c' to clear the buffer. 
mysql> USE mysql ; 
Reading table information for completion of table and column names 
You can turn off this feature to get a quicker startup with -A 
Database changed 
mysql> UPDATE user SET Password = password ( 'new-password' ) WHERE User = 'root' ; 
Query OK, 0 rows affected (0.00 sec) 
Rows matched: 2 Changed: 0 Warnings: 0 
mysql> flush privileges ; 
Query OK, 0 rows affected (0.01 sec) 
mysql> quit 
Bye

5．将MySQL的登录设置修改回来 
# vi /etc/my.cnf 
将刚才在[mysqld]的段中加上的skip-grant-tables删除 
保存并且退出vi。

6．重新启动mysqld 
# /etc/init.d/mysqld restart 
Stopping MySQL: [ OK ] 
Starting MySQL: [ OK ]

7. 测试连接数据库

# mysql -u root -p

Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.1.73 Source distribution

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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

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