Top 10 Backup and Recovery best practices

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Eine kurze Zusammenfassung des Metalink-Dokumentes Note:388422.1 mit Stand von Ende Aug 2006:

1. Turn on block checking
alter system set db_block_checking = true scope=both;

2. Turn on block tracking when using RMAN backups (if running 10g)
Anm: Das geht nur in der EnterpriseEdition.
alter database enable block change tracking;

3. Duplex log groups and members and have more than one archive log dest
Anm: Das geht nur in der EnterpriseEdition.
alter system set log_archive_dest_2='location=/new/location/archive2' scope=both;
alter database add logfile member '/new/location/redo21.log' group 1;

4. When backing up the database use the 'check logical' parameter
backup check logical database plus archivelog delete input;

5. Test your backup
restore validate database;

6. Have each datafile in a single backup piece
Anm: Ob dies im allgemeinen sinnvoll ist, bezweifel ich.
backup database filesperset 1 plus archivelog delete input;

7. Maintain your RMAN catalog/controlfile
Run regular catalog maintenance.
REASON: Delete obsolete will remove backups that are outside your retention policy.
If obsolete backups are not deleted, the catalog will continue to grow until performance
becomes an issue.

RMAN> delete obsolete;

REASON: crosschecking will check that the catalog/controlfile matches the physical backups.
If a backup is missing, it will set the piece to 'EXPIRED' so when a restore is started,
that it will not be eligible, and an earlier backup will be used. To remove the expired
backups from the catalog/controlfile use the delete expired command.

RMAN> crosscheck backup;
RMAN> delete expired backup;

8. Prepare for loss of controlfiles
set autobackup on
REASON: This will ensure that you always have an up to date controlfile available that has been
taken at the end of the current backup not during.

RMAN> configure controlfile autobackup on;

keep your backup logs
REASON: The backup log contains parameters for your tape access, locations on controlfile backups
that can be utilised if complete loss occurs.

9. Test your recovery
recover database test;

10. Do not specify 'delete all input' when backing up archivelogs

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