org.eclipse.persistence - CCommunication failure detected Warnings in Registry log

Document ID : KB000125131
Last Modified Date : 22/01/2019
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Issue:
When Registry is started, after sometime see the below in registry logs.

org.eclipse.persistence - Communication failure detected when attempting to perform read query outside of a transaction. Attempting to retry query. Error was: Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.2.v20111125-r10461): org.eclipse.persistence.exceptions.DatabaseException Internal Exception: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure The last packet successfully received from the server was 900,043 milliseconds ago. The last packet sent successfully to the server was 1 milliseconds ago. Error Code: 0 Call: SELECT ID AS a1, DATA AS a2 FROM DRADISCACHE LIMIT ?, ? bind => [2 parameters bound] Query: ReadAllQuery(referenceClass=DbDradisCache sql="SELECT ID AS a1, DATA AS a2 FROM DRADISCACHE LIMIT ?, ?").
Environment:
DevTest 10.0 and 10.3
Cause:
These warnings in logs are written by DevTest internal sql query retrying logic, that prevents queries from fault. If there are no errors after warning, that means that queries were successfully executed after first retry. Seems that sometimes first try of query fails due to some network problems on database server side and those warnings are seen again.
Resolution:
DevTest is working as designed and no changes needed.