MySQL 密码遗忘和登陆报错问题

2021/4/10 2:32:46

本文主要是介绍MySQL 密码遗忘和登陆报错问题,对大家解决编程问题具有一定的参考价值,需要的程序猿们随着小编来一起学习吧!

mysql登录密码忘记,其实解决办法很简单,只需要在mysql的主配置文件my.cnf里添加一行“跳过授权表”的参数选择即可!

在my.cnf中添加下面一行:
[root@test-huanqiu ~]# vim /etc/my.cnf              //在[mysqld]区域里添加
........
skip-grant-tables                       //跳过授权表

然后重启mysql服务,即可无密码登录
[root@test-huanqiu ~]# /etc/init.d/mysqld restart

登录后重置密码
[root@test-huanqiu ~]# mysql
mysql> select host,user,password from mysql.user;
+--------------------+------+-------------------------------------------+
| host               | user | password                                  |
+--------------------+------+-------------------------------------------+
| localhost          | root | *481ACA1BD6D1E86221244904E9C0FABA33B40B84 |
| host-192-168-1-117 | root |                                           |
| 127.0.0.1          | root |                                           |
| ::1                | root |                                           |
| localhost          |      |                                           |
| host-192-168-1-117 |      |                                           |
+--------------------+------+-------------------------------------------+
6 rows in set (0.00 sec)

mysql> update mysql.user set password=password("123456") where host="localhost" and user="root";
Query OK, 1 row affected (0.02 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> select host,user,password from mysql.user;
+--------------------+------+-------------------------------------------+
| host               | user | password                                  |
+--------------------+------+-------------------------------------------+
| localhost          | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
| host-192-168-1-117 | root |                                           |
| 127.0.0.1          | root |                                           |
| ::1                | root |                                           |
| localhost          |      |                                           |
| host-192-168-1-117 |      |                                           |
+--------------------+------+-------------------------------------------+
6 rows in set (0.00 sec)

mysql>

再次将my.cnf里添加的那一行注释,然后重启mysql
[root@test-huanqiu ~]# vim /etc/my.cnf
........
#skip-grant-tables

[root@test-huanqiu ~]# /etc/init.d/mysqld restart

[root@test-huanqiu ~]# mysql -p123456
mysql>

-----------------------------------------------------------------------------------------------------------------------
发现的一个坑:
mysql之前进行了全量备份,在恢复后,发现用之前的密码登陆不进去了!
使用上面的方法,无密码登陆后再重置密码,但是重置密码后发现仍然登陆不进去。

最后发现是因为mysql.user表内容被清空了!
mysql> select host,user,password from user;
Empty set (0.00 sec)

解决:
插入数据,再重置密码
mysql> insert into user(host,user,password) values("localhost","root","123456");
Query OK, 1 row affected, 3 warnings (0.01 sec)

mysql> select host,user,password from user;
+-----------+------+----------+
| host      | user | password |
+-----------+------+----------+
| localhost | root | 123456   |
+-----------+------+----------+
1 row in set (0.00 sec)

mysql> update mysql.user set password=password("123456") where host="localhost" and user="root";
Query OK, 1 row affected (0.01 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select host,user,password from user;
+-----------+------+-------------------------------------------+
| host      | user | password                                  |
+-----------+------+-------------------------------------------+
| localhost | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
+-----------+------+-------------------------------------------+
1 row in set (0.00 sec)
mysql> insert into user(host,user,password) values("127.0.0.1","root","123456");
Query OK, 1 row affected, 3 warnings (0.00 sec)

mysql> select host,user,password from user;
+-----------+------+-------------------------------------------+
| host      | user | password                                  |
+-----------+------+-------------------------------------------+
| localhost | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
| 127.0.0.1 | root | 123456                                    |
+-----------+------+-------------------------------------------+
2 rows in set (0.00 sec)

mysql> update mysql.user set password=password("123456") where  user="root";
Query OK, 1 row affected (0.00 sec)
Rows matched: 2  Changed: 1  Warnings: 0

mysql> select host,user,password from user;
+-----------+------+-------------------------------------------+
| host      | user | password                                  |
+-----------+------+-------------------------------------------+
| localhost | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
| 127.0.0.1 | root | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
+-----------+------+-------------------------------------------+

然后使用重置后的密码就能正常登陆了!

------------------------------------------------------------------------------------------------------------------
mysql登录报错1:
[root@test-huanqiu ~]# mysql -p123456
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (111)

[root@test-huanqiu ~]# ps -ef|grep mysql
root     28279     1  0 12:55 ?        00:00:00 /bin/sh /usr/local/mysql//bin/mysqld_safe --datadir=/data/mysql/data --pid-file=/data/mysql/data/mysql.pid
mysql    29059 28279  0 12:55 ?        00:00:01 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql/ --datadir=/data/mysql/data --plugin-dir=/usr/local/mysql//lib/plugin --user=mysql --log-error=/data/mysql/data/mysql-error.log --pid-file=/data/mysql/data/mysql.pid --socket=/usr/local/mysql/var/mysql.sock --port=3306
root     30726 11268  0 12:58 pts/2    00:00:00 grep mysql

可知,当前mysql.sock文件路径是/usr/local/mysql/var/mysql.sock,

解决办法:做软链接
[root@test-huanqiu ~]# ll /usr/local/mysql/var/mysql.sock
rwxrwxrwx. 1 mysql mysql 0 Nov 29 12:55 /usr/local/mysql/var/mysql.sock
[root@test-huanqiu ~]# rm -f  /var/lib/mysql/mysql.sock
[root@test-huanqiu ~]# ln -s /usr/local/mysql/var/mysql.sock /var/lib/mysql/mysql.sock

这样就没问题了
[root@test-huanqiu ~]# mysql -p123456
mysql>

----------------------------------------------------------------------------------------------------
启动mysql的时候报错:
Starting MySQL.... ERROR! The server quit without updating PID file (/data/mysql/data/mysql.pid).

尝试的解决办法:
(1)权限问题
可能是mysql.pid文件没有写的权限,将mysql的安装目录和数据目录的权限都设置成mysql启动用户权限。比如都修改为mysql:mysql权限
(2)可能进程里已经存在mysql进程
ps -ef|grep mysql  查出要是有mysql进程存在,就kill掉,再尝试重启mysql
(3)可能是多次在机器上安装mysql,有残余数据影响了服务的启动。
去mysql的数据目录看看,如果存在mysql-bin.index,就立刻删掉它,它就是罪魁祸首了!
(4)mysql在启动时没有指定配置文件时会使用/etc/my.cnf配置文件,请打开这个文件查看在[mysqld]节下有没有指定数据目录。
在[mysqld]下添加设置,如datadir = /data/mysql/data
(5)skip-federated字段问题
检查一下my.cnf文件中有没有没被注释掉的skip-federated字段,如果有就立即注释掉。
(6)错误日志目录不存在
去my.cnf文件下是否有log日志配置路径,如果有,查看下日志目录是否存在,日志目录权限要确保是mysql启动用户权限。
(7)selinux惹的祸,如果是centos系统,默认会开启selinux
闭它,打开/etc/selinux/config,把SELINUX=enforcing改为SELINUX=disabled后存盘退出重启机器试试。
(8)重新初始化mysql数据试试
切换到mysql的安装目录下
./scripts/mysql_install_db --basedir=/usr/local/mysql --datadir=/data/mysql/data --user=mysql

-----------------------------------------------------------
使用mysql服务端授权的信息登录mysql,报错如下:
ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.1.14' (111)

可能的原因有:
1)可能网络连接问题,远程ping 192.168.1.14 ,能ping通,排除此情况;
2)mysql服务端192.168.1.14的iptables里做了3306端口连接的白名单限制;
3)mysql服务端192.168.1.14的my.cnf文件里配置了bind_address地址绑定,不允许本机连接;
4)mysql服务端192.168.1.14的my.cnf文件里配置了skip_networking,这使用MySQL只能通过本机Socket连接(socket连接也是本地连接的默认方式),放弃对TCP/IP的监听;
5)排查DNS解析问题,检查mysql服务端192.168.1.14的my.cnf文件里是否设置了skip_name_resolve。这个参数加上后,不支持主机名的连接方式。
6)排查--port问题,有可能mysql服务端192.168.1.14的MySQL port不是默认3306,比如是3307端口,这样,远程连接的时候要加上--port=3307
7)排查用户和密码问题, 其实用户和密码的错误,不会出现111的,所以排除用户密码问题
ERROR 1045 (28000): Access denied for user 'root'@'XXXX' (using password: YES)



这篇关于MySQL 密码遗忘和登陆报错问题的文章就介绍到这儿,希望我们推荐的文章对大家有所帮助,也希望大家多多支持为之网!


扫一扫关注最新编程教程