CROSSCHECK

Syntax

Text description of the illustration crossche.gif

Purpose

To verify the existence of backups (backup sets or media-managed proxy copies) and copies (both archived logs and image copies) stored on disk or tape.

The CROSSCHECK command checks only objects marked AVAILABLE or EXPIRED, either by examining the files on disk for DISK channels or by querying the media manager for sbt channels. The CROSSCHECK command only processes files created on the same device type as the channels running the crosscheck.

RMAN does not delete any files that it is unable to find, but updates their repository records to EXPIRED. You can determine which files are marked EXPIRED by issuing a LIST EXPIRED command. Then, you can run DELETE EXPIRED to remove the repository records for all expired files.

If some backup pieces or copies were erroneously marked as EXPIRED, for example, because the media manager was misconfigured, then after ensuring that the files really do exist in the media manager, run the CROSSCHECK BACKUP command again to restore those files to AVAILABLE status. Note that the DELETE EXPIRED command removes both the repository records as well as any existing physical files whose records show the status EXPIRED.

See Also: Oracle9i Recovery Manager User's Guide to learn how to manage target database records in the catalog

Restrictions and Usage Notes

• The target instance must be started.

• A maintenance channel is not required when CROSSCHECK is used with a file that is on disk. If you use CROSSCHECK on nondisk files, and have objects created on device types that are not configured for automatic channels, then you must manually allocate maintenance channels for these objects. For example, if you created a backup on an sbt channel, but have only a DISK channel automatically configured, then you must manually allocate an sbt channel before the CROSSCHECK command can check the backup.

Keywords and Parameters

BACKUP	Crosschecks backup sets, backup pieces, and proxy copies. By default, RMAN crosschecks backups of the whole database. Both usable and unusable backups are included in the output, even those that cannot be restored, are expired or unavailable, or are incremental backups that cannot be restored because their parent full backup or copy no longer exists. See Also: The tables describing columns in the LIST output. Use the KEY column of the output to obtain the primary key usable in the CHANGE and DELETE commands
COPY	Crosschecks datafile copies, control file copies, archived redo logs, and image copies of archived redo logs. By default, CROSSCHECK checks copies of all files in the database with status AVAILABLE or EXPIRED.
	OF listObjList	Restricts the list of objects operated on to the object type specified in the listObjList clause. If you do not specify an object, CROSSCHECK defaults to all copies. See Also: "listObjList"
	maintQualifier	Restricts the command based on the specified options. See Also: "maintQualifier"
	Note: listObjList and maintQualifier are valid options on both the BACKUP and COPY commands.
recordSpec	Specifies the object whose availability status you are changing. See "recordSpec".
	DEVICE TYPE deviceSpecifier	Allocates automatic channels for the specified device type only. This option is valid only if you have configured automatic channels and have not manually allocated channels. For example, if you configure automatic disk and tape channels and run CROSSCHECK ... DEVICE TYPE DISK, then RMAN allocates only disk channels. See Also: "deviceSpecifier"

Examples

Crosschecking All Backups: Example

The following example queries the status of all backups and copies on tape and disk (note that because RMAN preconfigures a disk channel, you do not need to manually allocate a disk channel):

ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE sbt;
CROSSCHECK BACKUP;
CROSSCHECK COPY;

Crosschecking Within a Range of Dates: Example

The following example queries the media manager for the status of the backup sets in a given six month range. Note that RMAN uses the date format specified in the NLS_DATE_FORMAT parameter, which is 'DD-MON-YY' in this example:

ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE sbt;
CROSSCHECK BACKUP DEVICE TYPE sbt COMPLETED BETWEEN '01-JAN-00' AND '01-JUL-00';