ECS 连接 RDS telnet可以正常，连接提示
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 20,820,001 milliseconds ago. The last packet sent successfully to the se...
