How to monitor RMAN Backups ?

RMAN Backups Monitoring

select count(*) from  v$backup_async_io where status='IN PROGRESS';

Session information on backups

SELECT s.sid, username AS "User", program, module, action, logon_time "Logon", l.*
FROM v$session s, v$enqueue_lock l
WHERE l.sid = s.sid and l.type = 'CF' AND l.id1 = 0 and l.id2 = 2;

RMAN backup overall progress status

SELECT decode(context,1,'This Task:',2,'Agregate:','?') Context, sofar, totalwork, round(sofar/totalwork*100,2) "% Complete"
FROM v$session_longops
WHERE opname LIKE 'RMAN%'
AND opname LIKE '%aggregate%'
AND totalwork != 0
AND sofar <> totalwork
UNION
SELECT decode(context,1,'This Task:',2,'Agregate:','?') Context, sofar, totalwork, round(sofar/totalwork*100,2) "% Complete"
FROM v$session_longops
WHERE opname LIKE 'RMAN%'
AND opname NOT LIKE '%aggregate%'
AND totalwork != 0
AND sofar <> totalwork;