mysql忘記了超級用戶管理密碼，可以利用重新啓動mysql進程的時候帶 --skip-grant-tables參數來啓動數據庫，並空密碼登錄。這個就是相當於是數據庫第一次啓動的時候。隨後可以查看mysql.user表裏面的超級用戶，以及修改超級用戶的密碼
1# 關閉MYSQL instance，或者殺死進程
2# 重新啓動mysql，帶--skip-grant-tables語句
[mysql@mysql01 my.cnf.d]$ mysqld_safe --defaults-file='/data/mysqldata/3306/my.cnf' --skip-grant-tables &
[1] 32530
[mysql@mysql01 my.cnf.d]$ 180828 19:02:13 mysqld_safe Logging to '/data/mysqldata/3306/data/../mysql-error.log'.
180828 19:02:13 mysqld_safe Starting mysqld daemon with databases from /data/mysqldata/3306/data
[mysql@mysql01 my.cnf.d]$ 3# 空密碼登錄MySQL
[mysql@mysql01 my.cnf.d]$ msyql -S /data/mysqldata/3306/mysql.sock
bash: msyql: command not found...
[mysql@mysql01 my.cnf.d]$ mysql -S /data/mysqldata/3306/mysql.sock
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.31-log Source distribution
Copyright (c) 2000, 2016, 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.
(root@localhost)[(none)]> 4# 修改mysql.user表
(root@localhost)[(none)]> 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
(root@localhost)[mysql]>
(root@localhost)[mysql]> select user,host,password from user;
+------+-----------+-------------------------------------------+
| user | host | password |
+------+-----------+-------------------------------------------+
| root | localhost | *A0F874BC7F54EE086FCE60A37CE7887D8B31086B |
+------+-----------+-------------------------------------------+
1 row in set (0.00 sec)
(root@localhost)[mysql]> update user set password=password('password123') where user='root';
Query OK, 0 rows affected (0.00 sec)
Rows matched: 1 Changed: 0 Warnings: 0
(root@localhost)[mysql]> 5# 正常關閉數據庫
[mysql@mysql01 my.cnf.d]$ mysqladmin -S /data/mysqldata/3306/mysql.sock -uroot -p'password123' shutdown
Warning: Using a password on the command line interface can be insecure.
180828 19:04:54 mysqld_safe mysqld from pid file /data/mysqldata/3306/mysql.pid ended
[1]+ Done mysqld_safe --defaults-file='/data/mysqldata/3306/my.cnf' --skip-grant-tables
[mysql@mysql01 my.cnf.d]$ 6# 正常開啓數據庫
[mysql@mysql01 my.cnf.d]$ mysqld_safe --defaults-file='/data/mysqldata/3306/my.cnf' &
[1] 33094
[mysql@mysql01 my.cnf.d]$ 180828 19:05:04 mysqld_safe Logging to '/data/mysqldata/3306/data/../mysql-error.log'.
180828 19:05:04 mysqld_safe Starting mysqld daemon with databases from /data/mysqldata/3306/data
[mysql@mysql01 my.cnf.d]$7# 正常登錄數據庫
[mysql@mysql01 my.cnf.d]$ mysql -uroot -S '/data/mysqldata/3306/mysql.sock' -p'password123'
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 1
Server version: 5.6.31-log Source distribution
Copyright (c) 2000, 2016, 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.
(root@localhost)[(none)]> 至此mysql的root密碼修改完成