Example sharing of methods for changing root password in MySQL in CentOS environment

This article mainly tells you how to follow 12 methods to write high-quality JS code. Friends who need it can refer to it. I hope it can help everyone.

Environment related:
OS: CentOS release 6.9
IP: 192.168.1.10
MySQL: MariaDB-10.1.30

1. Confirmation before modification

To change the root password, you need to restart the mysql library, confirm that production can really restart the mysql library;

Confirm whether production has the use of directly using the root user to connect to the library , if so, make corresponding changes;

Please stop the application connected to the library before changing the password, that is, stop all production lines related to the library.

2. Stop the database and change the password

ps -ef|grep mysql|grep -v grep
# 找到对应的mysql服务器守护进程，查看是否有其他mysql服务守护进行存在
ps -ef|grep mysql|grep -v grep|xargs kill -9
# 杀掉root启动库的命令进程和库的守护进程，否则库会自动再次启动
# 杀掉进程，停库，杀掉进程之前请确保连接到库的应用全部停掉！！！
mysqld_safe --user=mariadb --skip-grant-tables &
# 忽略授权表启动库，此时如果使用密码则无法登陆库
# 连接到库的应用如果没有停掉，此时是无法成功连接到库的
mysql
use mysql;
select Host,User,Password from user where user='root';
exit;
# 进到mysql库中，查询当前的root密码的密值，保存密值用以回滚
# 比如我当前密码是vincent，密值是'*CDA83EBFF468E905FF304FE0D3D9F4D665C6579D'
mysql
use mysql;
update user set password=password('test') where user='root';
exit;
# 进到mysql库中，设置root密码
mysqladmin shutdown
mysqld_safe --user=mariadb &
# 重启库，登录测试
mysql -uroot -ptest -Dmysql
exit;
# 登录成功

3. Operation rollback

After you change the root password, you find many problems, such as unknown applications connecting to the library with the original root password (fucking historical problems), which need to be rolled back.

mysql -uroot -ptest -Dmysql
update user set password='*CDA83EBFF468E905FF304FE0D3D9F4D665C6579D' where user='root';
flush privileges;
exit;
# 使用上一步记录的root密码修改前的密值进行回滚
mysql -uroot -pvincent -Dmysql
exit;
# 回滚完成

4. Related knowledge points

You can directly use the password value to set the password. Currently, there is no way to directly set the password. The method of reversing the value into plain text of the password. To view the password value, you can use the password function:

mysql -uroot -pvincent
select password('vincent'),password('test');

But if you know the password value, you can know the secret value. Modify a user's password with root privileges, use it, and then restore it.
This situation is mostly used when a user forgets his password and resets his password. The same situation also occurs in the Oracle database.

Related recommendations:

Introduction to the method of changing the root password and installation and configuration tuning in Mysql

How to modify Mysql5.7 Root password sharing

MySQL's various methods to change the root password

The above is the detailed content of Example sharing of methods for changing root password in MySQL in CentOS environment. For more information, please follow other related articles on the PHP Chinese website!