Database Connection Failed Communications link failure due to underlying exception !, Underlying

Database Connection Failed Communications link failure due to underlying exception !, Underlying

(1) I encountered this problem today: When I use the DB Browser in Myeclipse to connect to mysql, communication link failure due to underlying exception occurs! Problems
The service is enabled, and SQL commands can also be executed. However, after a while, the connection will fail and the above problem will occur;
(2) Hurry up with Baidu. The methods of Baidu's various great gods are mainly
A) due to the limitations on the connection duration of mysql, mysql will be automatically disconnected when the time exceeds the limit. There are many solutions on the Internet. I will not explain them here;
B) My solution is to [close the firewall]. This evil firewall will be okay after it is shut down.
(3) If you have tried all the methods on the Internet and still haven't solved the problem, disable the firewall.