MySQL 无法远程连接?
MySQL 无法远程连接?
先看清楚报错信息,一般都有解答。
虽然报错信息写的有点难懂
0. 云服务器商防火墙 与 服务器防火墙
请登陆你的云服务器防火墙管理web进行相关配置。
服务器本身的防火墙配置可以使用:
sudo ufw status
STFW !
1. mysql deamon配置问题
/etc/mysql/mysql.conf.d/mysqld.cnf中,的
bind-address = 0.0.0.0 // 而不是127.0.0.1
然后
sudo systemctl restart mysql
2. mysql 认证方式
mysql_native_password : mysql vs. mysql2
报错信息如下 或类似:
code: 'ER_NOT_SUPPORTED_AUTH_MODE',
errno: 1251,
sqlMessage: 'Client does not support authentication protocol requested by server; consider upgrading MySQL client',
sqlState: '08004',
fatal: true
以javascript举例:应该安装mysql2, 用更新的认证方式
npm install mysql2
在你的javescript代码中使用
const mysql = require('mysql2');
3. 用户帐号相关问题
先查看所有用户的用户名
与 可访问host
(%表示什么ip都可以,通配符)
SELECT User, Host FROM mysql.user;
只有当
-
用户名存在
-
密码匹配
-
host可访问
-
用户权限足够
SHOW GRANTS FOR 'User'@'Host'; -- 查看用户权限
以上几点均满足时才行。
如何修改用户 User or Host or Password?
!!!不要直接修改mysql.user !!!
To modify the User
, Host
, or authentication information (password hash) in the mysql.user
table, you can use the appropriate SQL commands. Below are the steps for safely making changes:
1. Modify the User
Name
To rename a user, use the RENAME USER
command. Do not directly update the mysql.user
table.
RENAME USER 'old_user'@'old_host' TO 'new_user'@'old_host';
2. Modify the Host
To change the host for a user, use the RENAME USER
command as well:
RENAME USER 'user_name'@'old_host' TO 'user_name'@'new_host';
3. Modify the Authentication Code (Password)
To update a user’s password, use the ALTER USER
command:
ALTER USER 'user_name'@'host' IDENTIFIED BY 'new_password';
This command will automatically hash the password and update the authentication_string
column in mysql.user
.
4. Flush Privileges
After any manual modifications to mysql.user
, run the following to apply the changes:
FLUSH PRIVILEGES;
5. Verify Changes
Verify that the changes were applied correctly:
SELECT User, Host, authentication_string FROM mysql.user WHERE User = 'new_user';
3.1 如何创建新用户?
CREATE USER 'user'@'%' IDENTIFIED BY 'password';
GRANT ALL PRIVILEGES ON datebase.table TO 'dbuser'@'%'; -- 可以细设置权限,安全
FLUSH PRIVILEGES;
3.2 查看与修改用户权限
1. 登录到 MySQL
用具有管理员权限的用户(例如 root
)登录到 MySQL:
mysql -u root -p
2. 授予权限
为用户 hk416hasu
授予 learn
数据库的访问权限。
-
如果你想授予所有权限:
GRANT ALL PRIVILEGES ON learn.* TO 'hk416hasu'@'%'; FLUSH PRIVILEGES;
learn.*
表示授予learn
数据库中所有表的权限。@'%'
表示允许从任何 IP 地址访问。
-
如果只想授予基本的查询权限(安全性更高):
GRANT SELECT ON learn.* TO 'hk416hasu'@'%'; FLUSH PRIVILEGES;
3. 验证权限
可以验证用户的权限:
SHOW GRANTS FOR 'hk416hasu'@'%';
希望有解决你的问题!😄