Managing Dataguard.

To check status of Archive files in both Primary and Standby

SELECT process, status, thread#, sequence#,delay_mins, block#, blocks
FROM v$managed_standby  ;


Determine the most recently archived redo log file. 

SELECT MAX(sequence#), thread#
FROM v$archived_log
GROUP BY thread# ;



Determine the most recently archived redo log file at each redo transport destination.
SELECT destination, status, archived_thread#, archived_seq#
FROM v$archived_dest_status
WHERE status <> 'deferred'
AND status <> 'inactive';