Starting backup at 04-JUN-12
current log archived
released channel: t1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of backup command at 06/04/2012 10:36:16
RMAN-06059: expected archived log not found, lost of archived log compromises recoverability
ORA-19625: error identifying file /u01/oradata/airman/archive/1_8592_628791162.arc
ORA-27037: unable to obtain file status
SVR4 Error: 2: No such file or directory
Additional information: 3

Cause: This can happen for a variety of reasons; the file has been manually moved or deleted,
the archive log destination has recently been changed,
the file has been compressed, etc

Soluution:

Your options are either to restore the missing file(s), or to perform a crosscheck.
To perform a crosscheck, run the following command from within RMAN:

change archivelog all crosscheck;

Perform a full backup of the database

Note:
When an archive log crosscheck is performed, RMAN checks each archive log in turn to make sure
that it exists on disk (or tape). Those that are missing are marked as unavailable.
If you have got missing logs, this won’t bring them back. It will allow you to get past this error
and back-up the database though.