Home Database Mysql Tutorial 如何解决MySQL的root密码忘记的问题_MySQL

如何解决MySQL的root密码忘记的问题_MySQL

Jun 08, 2016 am 08:50 AM
mysql quot root user

如果哪天你忘记了线上MySQL数据库的root密码,怎么办?

大家往往会想到skip-grant-tables参数,具体步骤如下:

1. 关闭MySQL数据库,因为root密码忘记了,mysqladmin无法使用,此时,只能通过kill pid关闭程序。

在这里,科普一下kill 和kill -9的区别

默认参数下,kill 发送SIGTERM信号给进程,告诉进程,你需要被关闭,请自行停止运行并退出。

kill -9 发送SIGKILL信号给进程,告诉进程,你被终结了,请立刻退出。与SIGTERM相比,这个信号不能被捕获或忽略,同时接收这个信号的进程在收到这个信号时不能执行任何清理

所以,万不得已,不要通过kill -9杀掉进程,这可能导致MySQL数据库的物理结构损坏,无法重新启动。

2. 在my.cnf文件[mysqld]部分添加skip-grant-tables参数

3. 登录数据库,修改root账户的密码

以下是修改root密码的三种方式:

1> mysql> set password for 'root'@'localhost'=password('123'); 无需刷新权限表

2> mysql> update mysql.user set password=password("456") where user="root" and host="localhost";

mysql> flush privileges;

3> # mysqladmin -u root password "123"

4. 关闭数据库,注释掉skip-grant-tables参数,重新启动数据库。

上面这种方式虽然不错,但是有个问题,你必须重启数据库,对于线上环境,这可能是不被允许的。

下面来谈谈另一种方法,有点“黑暗科技”的味道

这个方法利用的是mysql.user表还是MyISAM引擎的特性。

1. 将该实例的mysql.user表copy到另一个实例的目录下,譬如,test数据库的目录下

 

\

 

2. 登录另一个实例数据库,修改上述三个文件的权限,并修改root密码

mysql> select user,host,password from test.user;

+------+-----------+-------------------------------------------+

| user | host | password |

+------+-----------+-------------------------------------------+

| root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |

+------+-----------+-------------------------------------------+

1 row in set (0.00 sec)

mysql> update test.user set password=password("hello") where user="root" and host="localhost";

Query OK, 1 row affected (0.15 sec)

Rows matched: 1 Changed: 1 Warnings: 0

3. 将上述三个文件copy回源数据库

 

\

 

4. 获取mysqld的pid,通过kill -HUP `pidof mysqld`方式让mysqld进程重新加载配置文件

 

\

 

[root@keepalived01 ~]# mysql -phello

Warning: Using a password on the command line interface can be insecure.

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

[root@keepalived01 ~]# kill -HUP 4283

[root@keepalived01 ~]# mysql -phello

Warning: Using a password on the command line interface can be insecure.

Welcome to the MySQL monitor. Commands end with ; or \g.

Your MySQL connection id is 2528

Server version: 5.6.26 MySQL Community Server (GPL)

Copyright (c) 2000, 2015, 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>

通过上述输出可以看出,kill -HUP之前,直接用密码hello登录被拒绝,kill -HUP之后,就可以直接登录了。

当然,以上方法仅供参考,在生产上慎用,毕竟安全压倒一切,天晓得哪里会出现问题。

以上就是本文的全部内容,希望可以帮助大家解决root密码忘记的困扰,谢谢大家的阅读。

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

PHP's big data structure processing skills PHP's big data structure processing skills May 08, 2024 am 10:24 AM

Big data structure processing skills: Chunking: Break down the data set and process it in chunks to reduce memory consumption. Generator: Generate data items one by one without loading the entire data set, suitable for unlimited data sets. Streaming: Read files or query results line by line, suitable for large files or remote data. External storage: For very large data sets, store the data in a database or NoSQL.

How to optimize MySQL query performance in PHP? How to optimize MySQL query performance in PHP? Jun 03, 2024 pm 08:11 PM

MySQL query performance can be optimized by building indexes that reduce lookup time from linear complexity to logarithmic complexity. Use PreparedStatements to prevent SQL injection and improve query performance. Limit query results and reduce the amount of data processed by the server. Optimize join queries, including using appropriate join types, creating indexes, and considering using subqueries. Analyze queries to identify bottlenecks; use caching to reduce database load; optimize PHP code to minimize overhead.

How to use MySQL backup and restore in PHP? How to use MySQL backup and restore in PHP? Jun 03, 2024 pm 12:19 PM

Backing up and restoring a MySQL database in PHP can be achieved by following these steps: Back up the database: Use the mysqldump command to dump the database into a SQL file. Restore database: Use the mysql command to restore the database from SQL files.

How to insert data into a MySQL table using PHP? How to insert data into a MySQL table using PHP? Jun 02, 2024 pm 02:26 PM

How to insert data into MySQL table? Connect to the database: Use mysqli to establish a connection to the database. Prepare the SQL query: Write an INSERT statement to specify the columns and values ​​to be inserted. Execute query: Use the query() method to execute the insertion query. If successful, a confirmation message will be output.

How to fix mysql_native_password not loaded errors on MySQL 8.4 How to fix mysql_native_password not loaded errors on MySQL 8.4 Dec 09, 2024 am 11:42 AM

One of the major changes introduced in MySQL 8.4 (the latest LTS release as of 2024) is that the "MySQL Native Password" plugin is no longer enabled by default. Further, MySQL 9.0 removes this plugin completely. This change affects PHP and other app

How to use MySQL stored procedures in PHP? How to use MySQL stored procedures in PHP? Jun 02, 2024 pm 02:13 PM

To use MySQL stored procedures in PHP: Use PDO or the MySQLi extension to connect to a MySQL database. Prepare the statement to call the stored procedure. Execute the stored procedure. Process the result set (if the stored procedure returns results). Close the database connection.

How to create a MySQL table using PHP? How to create a MySQL table using PHP? Jun 04, 2024 pm 01:57 PM

Creating a MySQL table using PHP requires the following steps: Connect to the database. Create the database if it does not exist. Select a database. Create table. Execute the query. Close the connection.

The difference between oracle database and mysql The difference between oracle database and mysql May 10, 2024 am 01:54 AM

Oracle database and MySQL are both databases based on the relational model, but Oracle is superior in terms of compatibility, scalability, data types and security; while MySQL focuses on speed and flexibility and is more suitable for small to medium-sized data sets. . ① Oracle provides a wide range of data types, ② provides advanced security features, ③ is suitable for enterprise-level applications; ① MySQL supports NoSQL data types, ② has fewer security measures, and ③ is suitable for small to medium-sized applications.

See all articles