One of the Oracle databases I help manage is the primary in a standby configuration, with two standby databases. I started finding repeated entries in the alert log on the primary for a failure to resolve the TNS connect identifier for log_archive_dest_3 and referencing the trace file for NSA3. That trace file had an error message I'd never seen before, and I can't find any information on it for the life of me: "LOG_ARCHIVE_DEST_2 depends upon me, but my destination index 2 does not match its destination index 1." This showed up several times in the trace file.
I was able to verify that all standbys are up-to-date with the primary and are responsive to tnsping. Can anyone shed some light on this error?