DGMGRL> add database O12_o12cvm2 as connect identifier is o12_o12cvm2 maintained as physical;
Error: ORA-12154: TNS:could not resolve the connect identifier specified

SQL> ALTER SYSTEM SET log_archive_dest_state_2='DEFER' SCOPE=MEMORY;

SQL> select status, Error from V$ARCHIVE_DEST where dest_id=2;

STATUS ERROR
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INACTIVE