linux下查看mysql数据库的默认密码并修改密码

查看默认密码

grep 'temporary password' /var/log/mysqld.log

或者

cat /var/log/mysqld.log | grep 'temporary password'

[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；

最后编辑于：2020.06.14 19:53:39