Mysql系列---【项目启动报com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure】

错误

Caused by: com.mysql.cj.exceptions.CJCommunicationsException: Communications link failure
The last packet successfully received from the server was 45,555 milliseconds ago. The last packet sent successfully to the server was 319 milliseconds ago.

排查思路

我的数据库用的是mysql8，经排查，linux服务器因为黑客攻击导致数据库关闭了，启动数据库即可。