Mysql root密码丢失后重置

假装密码丢失

mysql> set password=password('dsfsdfjsaldfjldsfsdf4dsf46453131321');
Query OK, 0 rows affected, 1 warning (0.00 sec)

1.关闭服务

[root@logan ~]# killall mysqld
[root@logan ~]# killall mysqld
mysqld: no process found                        

2.跳过授权表不验证；这里有两种方法：

1）直接启动服务

/usr/local/mysql/bin/mysqld_safe --user=mysql --skip-grant-tables &

2）对/etc/my.cnf 文件进行配置

[root@logan etc]# vim my.cnf
 1 [mysqld]
 2 skip-grant-tables

这里我用的第二种方法

3.重启mysql服务

[root@logan etc]# systemctl restart mysqldd

4.验证是否跳过授权表验证？

[root@logan etc]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.25 Source distribution

Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

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

mysql> 

可以看到，我们跳过的密码环节，直接进入到数据库

5.修改root 密码，我们先查看一下root密码存放位置

mysql> select * from mysql.user\G;
*************************** 1. row ***************************
                  Host: localhost
                  User: root
           Select_priv: Y
           Insert_priv: Y
           Update_priv: Y
           Delete_priv: Y
           Create_priv: Y
             Drop_priv: Y
           Reload_priv: Y
         Shutdown_priv: Y
          Process_priv: Y
             File_priv: Y
            Grant_priv: Y
       References_priv: Y
            Index_priv: Y
            Alter_priv: Y
          Show_db_priv: Y
            Super_priv: Y
 Create_tmp_table_priv: Y
      Lock_tables_priv: Y
          Execute_priv: Y
       Repl_slave_priv: Y
      Repl_client_priv: Y
      Create_view_priv: Y
        Show_view_priv: Y
   Create_routine_priv: Y
    Alter_routine_priv: Y
      Create_user_priv: Y
            Event_priv: Y
          Trigger_priv: Y
Create_tablespace_priv: Y
              ssl_type: 
            ssl_cipher: 
           x509_issuer: 
          x509_subject: 
         max_questions: 0
           max_updates: 0
       max_connections: 0
  max_user_connections: 0
                plugin: mysql_native_password
 authentication_string: *CB46BA0A9F8F5BFD02046E4AF418EE9FC7BE2E0D        　　　　#这个是root密码
      password_expired: N
 password_last_changed: 2019-07-03 14:16:59
     password_lifetime: NULL
        account_locked: N

我们需要把这个密码换成我们自己的

mysql> update mysql.user set authentication_string=password('123') where user='root';
Query OK, 1 row affected, 1 warning (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 1

提示成功后，我们需要删除my.cnf文件里的内容并重启服务

[root@logan etc]# systemctl restart mysqldd
[root@logan etc]# mysql
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

现在提示需要我们输入密码

[root@logan etc]# mysql -uroot -p123
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.25 Source distribution

Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

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

mysql> 

重置成功