Strange sudden shutdown of the portal running on Apache Tomcat

Issue

• Sudden shutdown with the following log snippet:

INFO  [http-nio-8080-exec-325][SidemenuController:88] Enter in sidemenu as connected=false and isFirstConnection=false screenname=XXXXX flag=false object=null
INFO [Thread-19] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["http-nio-8080"]
INFO [Thread-19] org.apache.coyote.AbstractProtocol.pause Pausing ProtocolHandler ["ajp-nio-8009"]

Environment

• Liferay Portal 6.1 and newer
• Liferay DXP 7.0 and newer

Resolution

• Solution 1:
  • Check in the affected environment if any of its service/application call port 8005;
    as it is the default shutdown port of Apache Tomcat, and this can cause sudden shutdowns
• Solution 2:
  • Check the affected environment if it has enough memory allocated;
    because the JVM can kill any process that cause out of memory issue