While MID server is being upgraded, ThreadPoolExecutor's pause() throws a NPE exception if the worker's source parameter is null or not present and the MID server got stuck in the UPGRADING state. - Known Error

While MID server is being upgraded, ThreadPoolExecutor's pause() throws a NPE exception if the worker's source parameter is null or not present and the MID server got stuck in the UPGRADING state. Description While MID server is being upgraded, ThreadPoolExecutor's pause() throws a NPE exception if the worker's source parameter is null or not present and the MID server got stuck in the UPGRADING state.

Steps to Reproduce

When issue happens:

> MID Server is stuck in "Upgrading" status on the instance. > MID Server Windows Service is running on the host > In agentlog, below error shows: 05/28/20 02:11:31 (150) AutoUpgrade.3600 Setting mid status to Upgrading 05/28/20 02:11:31 (150) AutoUpgrade.3600 Instance.updateAgentRecordState(), OperationalState=UPGRADING 05/28/20 02:11:31 (197) AutoUpgrade.3600 Pausing monitor: StatusMonitor 05/28/20 02:11:31 (228) AutoUpgrade.3600 SEVERE *** ERROR *** java.lang.NullPointerException java.lang.NullPointerException at java.lang.String.contains(String.java:2133) at com.service_now.mid.queue_worker.SystemCommand.shouldExecuteOnPause(SystemCommand.java:743) at com.service_now.monitor.PriorityThreadPoolProvider$PriorityThreadPoolExecutor.pause(PriorityThreadPoolProvider.java:246)

then repeated line: 05/28/20 03:11:30 (320) AutoUpgrade.3600 AutoUpgrade.run(), MID server Operational State=UPGRADING

Workaround Restart MID server windows service should resolve the issue.