由于有经验了，所以又弄了台虚拟机练手，承接上一篇博客（https://www.cnblogs.com/lelelong/p/10767049.html）
补充默认密码的截图
可以在文件 【/var/log/mysqld.log】 中获取，如图：
[[email?protected] mysql]# tail -100f /var/log/mysqld.log 2019-04-25T04:30:51.315933Z 0 [System] [MY-013169] [Server] /usr/sbin/mysqld (mysqld 8.0.15) initializing of server in progress as process 25808 2019-04-25T04:30:55.323029Z 5 [Note] [MY-010454] [Server] A temporary password is generated for [email?protected]: fu#0YkCp)uv8 2019-04-25T04:30:57.526215Z 0 [System] [MY-013170] [Server] /usr/sbin/mysqld (mysqld 8.0.15) initializing of server has completed 2019-04-25T04:30:59.986257Z 0 [System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.15) starting as process 26049 2019-04-25T04:31:00.635553Z 0 [Warning] [MY-010068] [Server] CA certificate ca.pem is self signed. 2019-04-25T04:31:00.667243Z 0 [System] [MY-010931] [Server] /usr/sbin/mysqld: ready for connections. Version: ‘8.0.15‘ socket: ‘/var/lib/mysql/mysql.sock‘ port: 3306 MySQL Community Server - GPL. 2019-04-25T04:31:00.765178Z 0 [System] [MY-011323] [Server] X Plugin ready for connections. Socket: ‘/var/run/mysqld/mysqlx.sock‘ bind-address: ‘::‘ port: 33060
?这里默认密码就是? ?fu#0YkCp)uv8
访问：
[[email?protected] mysql]# mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or g. Your MySQL connection id is 10 Server version: 8.0.15 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>
?在【/etc/my.cnf】中修改配置，将default-authentication-plugin=mysql_native_password? 去掉前面的#，如下图：
重启mysql服务
[[email?protected] mysql]# service mysqld restart
停止 mysqld： [确定]
正在启动 mysqld： [确定]
[[email?protected] mysql]#
其他命令：
show variables like ‘%auth%‘; #查看 default_authentication_plugin 的值 show variables like ‘default_password_lifetime‘; #查看 default_password_lifetime 的值 show variables like ‘%pass%‘; #查看模糊查询pass 属性的值 select user,host,plugin from mysql.user; #查看user表相关字段 set global validate_password_policy=0; #设置 validate_password_policy 全局值为0，可不遵循密码规则 set global validate_password_length=4; #设置 validate_password_length 密码长度最少位数 flush privileges; #修改生效
?
特别注意：8.0版本中?validate_password.policy /??validate_password.length? 最后一个链接符不是下划线_而是点.不然会报错，如下：
mysql> set global validate_password_policy=0; ERROR 1193 (HY000): Unknown system variable ‘validate_password_policy‘
参考博客：https://www.cnblogs.com/leohahah/p/9044904.html