Hello, Pega community, 

I am facing a sudden failure on all of our file listeners in our staging environment with what appears to be little in lieu of error logging or stack traces. 

We have 3 applications that share this environment. In this environment, we have 4 web nodes and 2 background processing nodes with the file listeners configured to start up on the background processing nodes. We are currently using Pega 8.2.2 and are running baseline performance testing prior to upgrading to 8.6.3.

When attempting to start the file listeners from Admin Studio, I am greeted with the red banner stating  "<node ID>: Exception occurred while restarting the listener FILE-Thread-xx" on every file listener. 

Things that I have attempted thus far: 

• Validate that the operator on the file listener rule form is accurate and has the appropriate access groups and credentials. 
• Log into a background processing node directly and test the connection from the rule form. 
  • This shows a positive access test, so I've concluded it's not an authorization problem.
• Restarted the entire environment and confirmed Kafka and other required services have come online. 
• Validated there are no unreachable stream nodes and cross-validated the node ID to the nodes in the "Systems and Nodes"
• Compared the stage environment to other regions that are not upgraded and concluded we do not have a code sync issue.

Is there any logging I can set for these listeners when attempting to start them up that I could use to isolate the root cause?

Thanks, 

Will McHugh