Tuning and Monitoring RMAN and the Automatic Diagnostic Workflow - OCP: Oracle Database 12c Administrator Certified Professional - page 262

In this case, we had some bad news because one of our backup set pieces is marked
EXPIRED , or missing. If we know that it's permanently gone, we can use the DELETE EXPIRED
command (discussed earlier in this chapter) to mark it as deleted. Sometimes the backup
set piece is expired just because the backup media is offline (for example, a bad disk cable).
Once the backup media is back online, you would rerun the CROSSCHECK command and the
backup set piece would be marked as AVAILABLE once it is again accessible by RMAN.
As with other administration commands, you can cross check the gambit of backups.
From database backups and archive-log backups to image copies, the CROSSCHECK command
covers them all.
Using the CATALOG Command
The CATALOG command is used to import one or more backup set pieces, image copies,
control-file copies, or archived redo logs into the recovery catalog. For example, say we had
executed a CROSSCHECK of our database backups and then deleted the expired backup set
pieces with the DELETE EXPIRED command. That would mark the expired backup set piece
as deleted in our control file and recovery catalog. This is okay until the missing backup
set piece reappears (say we restore it from a tape backup). In this case, we would have to
use the CATALOG command to reregister the backup set piece in the control file and recovery
catalog. Here is an example of the use of the CATALOG command:
RMAN> crosscheck backup of database;
using channel ORA_DISK_1
crosschecked backup piece: found to be 'EXPIRED'
backup piece handle=C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18
\O1_MF_NNNDF_TAG20131018T152908_4HNO9DX9_.BKP RECID=27 STAMP=668446156
Crosschecked 1 objects
RMAN> catalog backuppiece
'C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18
\O1_MF_NNNDF_TAG20131018T152908_4HNO9DX9_.BKP';
cataloged backup piece
backup piece handle=C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18
\O1_MF_NNNDF_TAG20131018T152908_4HNO9DX9_.BKP RECID=30 STAMP=668447953
The CROSSCHECK command can also import complete directories, as shown in this example:
RMAN> catalog start with
'C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18\';
searching for all files that match the pattern
C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18\
List of Files Unknown to the Database
=====================================
File Name: C:\ORACLE\FAST_RECOVERY_AREA\ORCL\BACKUPSET\2013_10_18\
O1_MF_ANNNN_TAG20131018T153543_4HNOP6OH_.BKP.old