Linux怎样查看mysql密码

相信很多小伙伴都经历过忘记密码，如果在Linux下忘记MySQL密码该怎么办？

Linux查看mysql密码具体方法。

查看默认密码

或者

 [root@VM_0_11_centos ~]# grep 'temporary password' /var/log/mysqld.log
 2020-05-07T16:57:52.623306Z 1 [Note] A temporary password is generated for root@localhost: Ukyool6&htfu

修改密码

初次修改密码时，需要注意的是密码中需要含有字母、数字、特殊字符 （要含有大小字母且长度不能小于8）

 [root@VM_0_11_centos ~]# mysql -uroot -p
 Enter password:
 Welcome to the MySQL monitor.  Commands end with ; or \g.
 Your MySQL connection id is 1721
 Server version: 5.7.30 MySQL Community Server (GPL)
 
 Copyright (c) 2000, 2020, 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> show databases;
 ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
 mysql> alter user root@localhost identified by 'root!@#123';
 ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
 mysql>  SHOW VARIABLES LIKE 'validate_password%';
 ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
 mysql> alter user root@localhost identified by 'Root!@#123';
 Query OK, 0 rows affected (0.00 sec)
 
 mysql> SHOW VARIABLES LIKE 'validate_password%';
 +--------------------------------------+--------+
 | Variable_name                        | Value  |
 +--------------------------------------+--------+
 | validate_password_check_user_name    | OFF    |
 | validate_password_dictionary_file    |        |
 | validate_password_length             | 8      |
 | validate_password_mixed_case_count   | 1      |
 | validate_password_number_count       | 1      |
 | validate_password_policy             | MEDIUM |
 | validate_password_special_char_count | 1      |
 +--------------------------------------+--------+
 7 rows in set (0.01 sec)
 
 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> select Host,User from user;
 +-----------+---------------+
 | Host      | User          |
 +-----------+---------------+
 | localhost | mysql.session |
 | localhost | mysql.sys     |
 | localhost | root          |
 +-----------+---------------+
 3 rows in set (0.00 sec)
 
 mysql>

关于 mysql 密码策略相关参数； 

1）、validate_password_length 固定密码的总长度；

2）、validate_password_dictionary_file 指定密码验证的文件路径； 

3）、validate_password_mixed_case_count 整个密码中至少要包含大/小写字母的总个数； 

4）、validate_password_number_count 整个密码中至少要包含阿拉伯数字的个数； 

5）、validate_password_policy 指定密码的强度验证等级，默认为 MEDIUM； 

关于 validate_password_policy 的取值： 

0/LOW：只验证长度； 

1/MEDIUM：验证长度、数字、大小写、特殊字符； 

2/STRONG：验证长度、数字、大小写、特殊字符、字典文件； 

6）、validate_password_special_char_count 整个密码中至少要包含特殊字符的个数；