Unexpected error on Server [null] while publishing a process

Products

• CA Release Automation - Release Operations Center (Nolio)

Issue/Introduction

Error Unexpected error on Server [null] while publishing a process which is blocking the deployment.

nolio_dm_all.log:

"[http-nio-8080-exec-4] ERROR (com.nolio.releasecenter.utils.MessagesDataUtils:186) - Unexpected error 
[1747224014062] com.nolio.platform.server.dataservices.api.execmng.ExecutionServersServiceException: 
Could not get superNodes list for execution server es_EXECUTIONSERVER1

...
Caused by: org.springframework.remoting.RemoteConnectFailureException: Could not connect to HTTP invoker 
remote service at [HTTPS://EXECUTIONSERVER1:8443/execution/UpdateCommunicationService]; nested exception 
is java.net.ConnectException: Connection refused: connect
...
Caused by: java.net.ConnectException: Connection refused: connect"
...

Environment

Release Automation - All versions

Cause

Seems it hangs there while attempting to get a list of ES, until it gets the communication message
failure for superNodes list. The "Unexpected error: Could not get superNodes list for execution 
server" message usually indicates that the system cannot establish a connection with or retrieve 
information from the designated "superNodes" (or "super nodes") responsible for executing tasks. 
This can be caused by network issues, server outages, or misconfigurations. 

Resolution

Due to connection refused see the ref. article in item 6. of the Troubleshooting steps in the 
Resolution section:

Troubleshooting connectivity between NAC and NES