linux 后台日志 mysql 错误异常的解释(推荐)

1、Caused by: com.MySQL.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 56,201,339 milliseconds ago.  The last packet sent successfully to the server was 56,201,339 milliseconds ago. is longer than the server configured value of ‘wait_timeout’