RMAN-06059: expected archived log not found

The customer alerted us that the scripted RMAN backups for smstrain were failing. I confirmed this by looking in the log …

oracle> cd /mserv/oracle/logs/RMAN

oracle> ls -lrt *smstrain*

oracle> pg sms_rmanhot_smstrain_Thu.log

…

Starting backup at 04-JUN-09 05:10:28

current log archived

released channel: t1

RMAN-00571:

===========================================================

RMAN-00569: =============== ERROR MESSAGE

STACK FOLLOWS ===============

RMAN-00571:

===========================================================

RMAN-03002: failure of backup plus archivelog

command at 06/04/2009 05:14:05

RMAN-06059: expected archived log not found, lost of archived log compromises recoverability

ORA-19625: error identifying file /dbsms/smstrain/oradata/smstrain/archive/arch_641734909_1_6050.arc

ORA-27037: unable to obtain file status

SVR4 Error: 2: No such file or directory

Additional information:

3

…

… which seems to say that an expected archive-log was not found. I guess another backup deleted it, or perhaps it was ‘tidied away’ to save space.
The fix was to manually resync rmans catalog for the instance …

oracle>  .oraenv

oracle> smstrain

oracle> rman target /

rman> crosscheck archivelog all;

rman> exit

This prompted me to a) resync all instances on the server, and b) run a full backup on each.