ORA-16883
unable to translate the DGConnectIdentifier property to a valid connect identifier
Cause
One or more members in the Data Guard configuration could not resolve the connect identifier specified by the DGConnectIdentifier property. The connectivity between the members could not be established for this reason. This might be caused by a missing or invalid tnsnames.ora entry, or an invalid connect descriptor, a missing naming method in sqlnet.ora, or another naming issue.
Action
Use the command VALIDATE NETWORK CONFIGURATION FOR ALL in DGMGRL and verify which database or instance could not resolve the connect identifier. Fix the problem depending on the naming method used in your environment.