MySQL 5.7忘记root密码后修改的详细教程
前言
一直以来,mysql的应用和学习环境都是mysql 5.6和之前的版本,也没有去关注新版本mysql 5.7的变化和新特性。今天帮人处理忘记root密码的时时候,发现以前的方法不奏效了。
具体情况如下所示:
案例环境如下:
操作系统 : red hat enterprise linux server release 6.6 (santiago)
数据库版本: 5.7.18 mysql community server (gpl)
忘记密码,输入错误的密码时遇到下面错误信息:
[root@mytestlnx02 ~]# mysql -u root -p enter password: error 1045 (28000): access denied for user 'root'@'localhost' (using password: yes) [root@mytestlnx02 ~]#
检查mysql服务是否启动,如果启动,关闭mysql服务
[root@mytestlnx02 ~]# ps -ef | grep -i mysql root 22972 1 0 14:18 pts/0 00:00:00 /bin/sh /usr/bin/mysqld_safe --datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock --pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr --user=mysql mysql 23166 22972 0 14:18 pts/0 00:00:00 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib/mysql/plugin --user=mysql --log-error=/var/log/mysqld.log --pid-file=/var/run/mysqld/mysqld.pid --socket=/var/lib/mysql/mysql.sock root 23237 21825 0 14:22 pts/0 00:00:00 grep -i mysql [root@mytestlnx02 ~]# service mysqld stop stopping mysqld: [ ok ] [root@mytestlnx02 ~]#
找到mysql的my.cnf配置文件,在/etc/my.cnf (有些版本是/etc/mysql/my.cnf)在里面增加下面一段信息:
[mysqld] skip-grant-tables
然后启动mysql,进入mysql后,修改root密码,操作过程中遇到error 1054 (42s22): unknown column 'password' in 'field list'
,查了一下user表的表结构,发现原来mysql 5.7下,user表已经没有password字段。加密后的用户密码存储于authentication_string字段。
具体操作过程如下所示:
[root@mytestlnx02 ~]# service mysqld start starting mysqld: [ ok ] [root@mytestlnx02 ~]# mysql -u root welcome to the mysql monitor. commands end with ; or \g. your mysql connection id is 4 server version: 5.7.18 mysql community server (gpl) copyright (c) 2000, 2017, 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> 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 password=password('kd8k&dfdl023') -> where user='root'; error 1054 (42s22): unknown column 'password' in 'field list' mysql> update mysql.user set authentication_string=password('kd8k&dfdl023') where user='root'; query ok, 1 row affected, 1 warning (0.00 sec) rows matched: 1 changed: 1 warnings: 1 mysql> flush privileges; query ok, 0 rows affected (0.00 sec) mysql> exit
在my.cnf文件中,把刚才加入的那一行“skip-grant-tables”注释或删除掉。 然后重启mysql服务后需要执行命令set password=password('newpassword');
后,问题搞定。
[root@mytestlnx02 ~]# service mysqld start starting mysqld: [ ok ] [root@mytestlnx02 ~]# mysql -u root -p enter password: welcome to the mysql monitor. commands end with ; or \g. your mysql connection id is 4 server version: 5.7.18 copyright (c) 2000, 2017, 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> use mysql; error 1820 (hy000): you must reset your password using alter user statement before executing this statement. mysql> set password=password('kd8k&dfdl023'); query ok, 0 rows affected, 1 warning (0.00 sec)
后面查询了一下相关资料,发现mysql 5.7在安全方面有下一些新特性。
1. 用户表 mysql.user 的 plugin字段不允许为空, 默认值是 mysql_native_password,而不是 mysql_old_password,不再支持旧密码格式;
2. 增加密码过期机制,过期后需要修改密码,否则可能会被禁用,或者进入沙箱模式; 是否启用密码过期由参数default_password_lifetime控制。
mysql> show variables like 'default_password_lifetime'; +---------------------------+-------+ | variable_name | value | +---------------------------+-------+ | default_password_lifetime | 0 | +---------------------------+-------+ 1 row in set (0.00 sec) mysql>
3:增加了密码安全等级以及密码复杂度设置。参数如下:
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 (0.00 sec)
4. 使用 mysql_install_db 初始化时,默认会自动生成随机密码,随机密码放在/var/log/mysqld.log中,并且不创建除 root@localhost和mysql.sys@localhost 外的其他账号,也不创建 test 库;
[root@mytestlnx02 mysql]# yum localinstall mysql-community-{server,client,common,libs}-* [root@mytestlnx02 mysql]# rpm -qa | grep -i mysql mysql-community-client-5.7.18-1.el6.i686 mysql-community-libs-5.7.18-1.el6.i686 perl-dbd-mysql-4.013-3.el6.x86_64 mysql-community-server-5.7.18-1.el6.i686 mysql-community-common-5.7.18-1.el6.i686 mysql-community-libs-compat-5.7.18-1.el6.i686 [root@mytestlnx02 mysql]# service mysqld start initializing mysql database: [ ok ] installing validate password plugin: [ ok ] starting mysqld: [ ok ] [root@mytestlnx02 mysql]# [root@mytestlnx02 mysql]# grep 'temporary password' /var/log/mysqld.log 2017-05-05t06:10:57.802143z 1 [note] a temporary password is generated for root@localhost: w99s(m-q_ml: mysql> select user ,host from user; +-----------+-----------+ | user | host | +-----------+-----------+ | mysql.sys | localhost | | root | localhost | +-----------+-----------+ 2 rows in set (0.00 sec)
总结
以上就是这篇文章的全部内容了,希望本文的内容对大家的学习或者工作能带来一定的帮助,如果有疑问大家可以留言交流,谢谢大家对的支持。
推荐阅读
-
Linux mysql如何更改root密码以及忘记root密码的修改方法
-
Windows 8.1下MySQL5.7 忘记root 密码的解决方法
-
Mysql的Root密码忘记,查看或修改的解决方法(图文介绍)
-
MySQL5.7.20解压版安装和修改root密码的教程
-
Mysql5.7在忘记密码的情况下如何修改密码?
-
MySQL5.7忘记root密码后最简单的修改密码方法介绍
-
MySQL 5.7忘记root密码后修改的详细教程
-
mysql5.7及mysql 8.0版本修改root密码的方法小结
-
MySQL 5.7的user表中,root用户密码修改教程
-
MySQL root密码忘记后更优雅的解决方法