Linux MySQL初始化问题

一、密码

MySQL5.7以上root用户会随机生成一个密码，存于error日志中，RPM包安装默认是在/var/log/mysqld。log中

mysql> select @@log_error;
+---------------------+
| @@log_error         |
+---------------------+
| /var/log/mysqld.log |
+---------------------+
1 row in set (0.00 sec)

 通过# grep "password" /var/log/mysqld.log 命令可获取MySQL默认临时密码

2020-12-01T12:00:55.050763Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: t%/k5CpNh0fi

其中t%/k5CpNh0fi就是默认的临时密码

登录服务后，需要立即更改密码，否则做其他任何操作都会报错

修改密码

若只是修改一个简单密码也会报错，密码不够安全

mysql>  ALTER USER USER() IDENTIFIED BY '12345678';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements

查看密码安全等级

mysql> show variables like'validate_password%';
+--------------------------------------+--------+
| Variable_name                        | Value  |
+--------------------------------------+--------+
| validate_password.check_user_name    | ON     |
| 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      |
+--------------------------------------+--------+

mysql> select @@validate_password.policy;
+----------------------------+
| @@validate_password.policy |
+----------------------------+
| MEDIUM                     |
+----------------------------+
mysql> select @@validate_password.length;
+----------------------------+
| @@validate_password.length |
+----------------------------+
|                          8 |
+----------------------------+

Policy	Tests Performed
0 or LOW	Length
1 or MEDIUM Length;	numeric, lowercase/uppercase, and special characters
2 or STRONG Length;	numeric, lowercase/uppercase, and special characters; dictionary file

 可根据自己需求修改：

set global validate_password_policy=0;
set global validate_password.length=6;

忘记密码，修改密码

在 /etc/my.cnf文件中添加  skip-grant-tables ，（windows下修改的是my.ini），定位到[mysqld]文本下

#vim /etc/my.cnf

 

重启MySQL服务，并修改密码，最后再将/etc/my.cnf文件中skip-grant-tables去掉，并再次重启MySQL服务；

systemctl restart mysqld

修改密码

alter user 'root'@'localhost' identified by '密码';

二、navicate链接错误

1、2003（10060）错误

    原因是防火墙问题

• 关闭防火墙

//停止
systemctl stop firewalld.service
//禁止开机启动
systemctl disable firewalld.service

• 设置防火墙开放端口

//这里发现防火墙是开启的，再来查看防火墙控制的端口
systemctl status firewalld
//查看防火墙控制的端口
firewall-cmd --list-all
//永久开启3306端口
sudo firewall-cmd --zone=public --add-port=3306/tcp --permanent
//重载防火墙
sudo firewall-cmd --reload

 2、1130错误

默认root用户只允许本机访问，查看可访问用户

select host,user from user; 

修改user表的值即可

update user set host = '%' where user = 'root';
flush privileges;

mysql> select host,user from user;
+-----------+------------------+
| host      | user             |
+-----------+------------------+
| %         | root             |
| localhost | mysql.infoschema |
| localhost | mysql.session    |
| localhost | mysql.sys        |
+-----------+------------------+

三、dhcp无法无法访问网络

重启网络服务即可

systemctl restart network

若提示先面错误，测需要关闭NetworkManager

Job for network.service failed because the control process exited with error code. See "systemctl status network.service" and "journalctl -xe" for details.

#临时关闭
systemctl stop NetworkManager
#永久关闭
systemctl disable NetworkManager

之后重启网络服务即可

【究极详细版】Ubuntu安装配置MySQL_ubuntu配置mysql-优快云博客