連線ubuntu(伺服器) MySQL 步驟（親測好用）

MySQL -h192.168.0.104 -uroot -pXXX

 mysql: [Warning] Using a password on the command line interface can be insecure.
 ERROR 2003 (HY000): Can't connect to MySQL server on '192.168.1.104' (111)

解決方案：

1、授予遠端登入許可權
grant all privileges on *.* To '使用者名稱'@'%' identified by '密碼' with
 
 grant option；
-- 5.7 後加使用者名稱登入驗證外掛 如果密碼過於簡單 可能會出現（如果沒有可直接進行第二步）：
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements  
-- 驗證解決方案
     mysql> select @@log_error;
        +---------------------+
        | @@log_error         |
        +---------------------+
        | /var/log/mysqld.log
 
 |
        +---------------------+
1 row in set (0.00 sec)
    mysql> set global validate_password_policy=0;
            Query OK, 0 rows affected (0.00 sec)
    mysql> set global validate_password_mixed_case_count=2;
            Query OK, 0 rows affected (0.00 sec)
    mysql> set global validate_password_length=4
 
;
            Query OK, 0 rows affected (0.00 sec)
    mysql> set global validate_password_special_char_count=0;
            Query OK, 0 rows affected (0.00 sec)
    mysql> SHOW VARIABLES LIKE 'validate_password%';
            +--------------------------------------+-------+
            | Variable_name                        | Value |
            +--------------------------------------+-------+
            | validate_password_dictionary_file    |       |
            | validate_password_length             | 4     |
            | validate_password_mixed_case_count   | 2     |
            | validate_password_number_count       | 0     |
            | validate_password_policy             | LOW   |
            | validate_password_special_char_count | 0     |
            +--------------------------------------+-------+
6 rows in set (0.00 sec)
    mysql> flush privileges;
-- 重新遠端授權
     mysql> grant all privileges on *.* To '使用者名稱'@'%' identified by '密碼' with grant option；
     Query OK, 0 rows affected (0.00 sec)
     mysql>exit

2、關閉防火牆（本地服務關閉，連線電腦也需要關閉防火牆）     
    [email protected]: sudo ufw disable 
            防火牆在系統啟動時自動禁用

3、測試遠端連線    [email protected]:ifconfig    -- 檢視當前ip地址    [email protected]:mysql -h192.168.1.104 -uroot -proot    ERROR 2003 (HY000): Can't connect to MySQL server on 'h192.168.1.104' (111)-- 但是通過127.0.0.1或者loclalhost可以連線上，通過固定ip連接出現錯誤4、檢視配置檔案   [email protected]: sudo vim /etc/mysql/my.cnf# bind-address = 127.0.0.1（如果有這句話就註釋）-- 開啟之後自己5.7版本的並沒有，然後在找檔案   [email protected]: sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf-- 發現裡面有這句話 # bind-address = 127.0.0.1（進行註釋）5、重啟mysql服務         [email protected]: service mysql restart      [email protected]:/etc/mysql$ mysql -h192.168.1.104 -uroot -pXXX    mysql: [Warning] Using a password onthe command line interface can be insecure.    Welcome tothe MySQL monitor.  Commands endwith ; or \g.    Your MySQL connection idis4    Server version: 5.7.17-0ubuntu0.16.04.2 (Ubuntu)    Copyright (c) 2000, 2016, Oracle and/orits affiliates. All rights reserved.    Oracle is a registered trademark of Oracle Corporation and/orits    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>6、如果連線還出現失敗就要檢視埠號是否為3306   mysql> show variables;          | port                | 3306   [email protected]: sudo vim /etc/mysql/mysql.conf.d/mysqld.cnf      （修改配置檔案中的埠號即可，然後重啟服務即可）