本文已参与「新人创作礼」活动，一起开启掘金创作之路。
一、 配置免密登录
切换root账号登录，找到mysql的my.cnf配置文件
su root
输入密码：
vim /etc/my.cnf
输入： i
添加： skip-grant-tables
返回：esc
退出：:wq
二、重启mysqld使其配置生效
执行如下代码重启服务：
systemctl restart mysqld
三、进入mysql清空旧密码
mysql -u root -p //提示输入密码时直接敲回车（免密登录）。
use mysql //选择数据库
update user set authentication_string = ‘’ where user = ‘root’; //将密码置空
quit //退出
[root@localhost ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 22
Server version: 8.0.26 MySQL Community Server - GPL
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
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>
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> update user set authentication_string = '' where user = 'root';
Query OK, 1 row affected (0.00 sec)
mysql> quit
Bye
四、取消my.cnf免密登录并重启mysqld使其配置生效
vim /etc/my.cnf
输入： i
删除这一行： skip-grant-tables
返回：esc
退出：:wq
再次重启服务：
systemctl restart mysqld
五、修改密码
mysql -u root -p //提示输入密码时直接敲回车，刚刚已经将密码置空了
ALTER USER ‘root’@‘localhost’ IDENTIFIED BY ‘admin12@xli’;
//密码形式过于简单则会报错,简单密码设置另外可以设置
[root@localhost ~]# mysql -uroot -p Enter password: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 22 Server version: 8.0.26 MySQL Community Server - GPL
Copyright (c) 2000, 2021, Oracle and/or its affiliates.
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> mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'Linux@112'; Query OK, 0 rows affected (0.00 sec) mysql> quit
至此密码就修改成功了，哎真坑，对于初次接触linux的小伙伴，简直是种煎熬，方方面面啥的都不懂，各种指令各种套路，还好网上有先驱们指路，不然果断放弃，哈哈。
