mysql.connector通过SSH隧道连接RDS MySQL失败，pymysql可正常连接

SSH隧道已成功建立，但通过隧道连接RDS MySQL时抛出错误：2003 (HY000): Can't connect to MySQL server on '0.0.0.0:52678' (10049)。使用pymysql库能正常连接，但用mysql.connector就失败，相关代码如下：

# Create an SSH tunnel to the RDS instance via the bastion host
with sshtunnel.SSHTunnelForwarder(
        ssh_config['ssh_host'],
        ssh_username=ssh_config['ssh_username'],
        ssh_private_key=ssh_config['ssh_private_key'],
        remote_bind_address=(rds_config['host'], rds_config['port'])
) as tunnel:
    print("SSH tunnel created successfully")

    # Connect to the RDS instance through the SSH tunnel
    conn = mysql.connector.connect(
        user=rds_config['user'],
        password=rds_config['password'],
        host=tunnel.local_bind_host,
        port=tunnel.local_bind_port,
        database=rds_config['database']
    )

• 强制指定本地连接地址为127.0.0.1
  sshtunnel默认的local_bind_host是0.0.0.0，部分环境下mysql.connector对这个地址的解析有兼容性问题，直接把连接的host改成127.0.0.1即可，端口仍使用tunnel.local_bind_port。

• 升级mysql.connector到最新版
  旧版本的mysql.connector在处理动态端口或0.0.0.0绑定的socket时存在bug，执行以下命令升级：

  pip install --upgrade mysql-connector-python
  

• 显式设置隧道的本地绑定地址
  创建SSHTunnelForwarder时手动指定local_bind_address参数，强制绑定到127.0.0.1，避免地址解析问题：

  with sshtunnel.SSHTunnelForwarder(
          ssh_config['ssh_host'],
          ssh_username=ssh_config['ssh_username'],
          ssh_private_key=ssh_config['ssh_private_key'],
          remote_bind_address=(rds_config['host'], rds_config['port']),
          local_bind_address=('127.0.0.1', 0)  # 0表示自动分配可用端口
  ) as tunnel:
  

• 检查本地端口监听状态
  用命令确认隧道的本地端口是否正常监听：

  • Windows：netstat -ano | findstr 52678
  • Linux/macOS：lsof -i :52678
    如果发现端口只绑定在0.0.0.0，就直接用127.0.0.1连接，不要用tunnel.local_bind_host返回的地址。

内容的提问来源于stack exchange，提问作者Lavish Karankar