Re: Deletion of old Archived Redo Logs
- From: Randal Bennett <rdbennett2000@xxxxxxxxx>
- To: "patrice.boivin@xxxxxxxxx" <patrice.boivin@xxxxxxxxx>, ORACLE-L <oracle-l@xxxxxxxxxxxxx>
- Date: Wed, 18 Jul 2012 20:50:07 -0700 (PDT)
Patrice,
Sort of. It implies Oracle will not so much overwrite as delete the logs
when the available space in the fast recovery area is depleted.
We relied on this initially, but we ran into the same issue you described, not
only on our 11.2.0.3 databases but on some other versions as well.
We believe it's because our backups were being written to the fast
recovery area, too, so Oracle thought it had enough room to preclude
deleting the old log archives until the backup process ran and filled
the available space, then it suspended the backup since it was out of
room. It was almost like the available space had to be nearly zero
before the software would start to delete the archived logs, which was
far too late.
We ended
up with an rman script for the backups that ended with: (1)
crosschecking the backups (crosscheck backup;), (2) crosschecking the
archived logs (crosscheck archivelog all;), then (3) deleting the
obsolete files (delete obsolete;).
This allows rman to apply the retention policy (e.g., 7 days for the
backups, backed up at least once for the archived logs) before it
actually deletes anything. Combined with the Oracle recommended backup
strategy (attention to detail in the documents when there is a
requirement to retain the backups for more than one day), this reduced
the required fast recovery area by about 50 percent.
HTH
-- Randy
________________________________
From: Patrice sur GMail <patrice.boivin@xxxxxxxxx>
To: ORACLE-L <oracle-l@xxxxxxxxxxxxx>
Sent: Monday, July 16, 2012 6:11 AM
Subject: Deletion of old Archived Redo Logs
Deletion of Archived Redo Logs
As explained in "Basic Concepts of Backup and Repository Maintenance", the
recommended maintenance strategy is to configure a fast recovery area, a
backup retention policy, and an archived redo log deletion policy. By
default, the archived redo logs deletion policy is configured to NONE. In
this case, the fast recovery area considers the logs eligible for deletion
if they have been backed up at least once to disk or tape or the logs are
obsolete according to the backup retention policy.
Archived redo logs can be deleted automatically by the database or by any
of the user-initiated RMAN commands listed in Table 12-1. For logs in the
recovery area, the database retains them as long as possible and
automatically deletes eligible logs when disk space is required. You can
delete eligible logs from any location, inside or outside the recovery
area, with BACKUP ... DELETE INPUT or DELETE ARCHIVELOG. Both of these
commands obey the archive redo log deletion policy when the policy is any
setting other than NONE. You can override the archived redo log deletion
policy settings by using the FORCE option in the DELETE command.
English is not my first language, but doesn't this imply that if the
fast_recovery_area is short of space, RMAN will overwrite older logs?
It's not doing it on our server, we are at 11.2.0.3..
-- Patrice
<http://www.viadeo.com/fr/profile/patrice.boivin>
[image: Facebook]
<http://www.facebook.com/profile.php?id0000206805521> [image:
LinkedIn] <http://ca.linkedin.com/pub/patrice-boivin/a/933/5a9> [image:
Twitter] <http://www.twitter.com/PatriceBoivin> [image:
Amazon]<http://www.amazon.com/gp/redirect.html?ie=UTF8&location=http%3A%2F%2Fwww.amazon.com%2Fgp%2Fregistry%2Fregistry.html%3Fie%3DUTF8%26type%3Dwishlist%26id%3D2JU0BBL2AGGSD&tagÊsper-20>
[image:
Digg] <http://digg.com/patriceboivin> [image:
Google]<http://https://sites.google.com/site/patriceboivin/>
Get a signature like this.
<http://r1.wisestamp.com/r/landing?promo&dest=http%3A%2F%2Fwww.wisestamp.com%2Femail-install%3Futm_source%3Dextension%26utm_medium%3Demail%26utm_campaign%3Dpromo_19>
CLICK
HERE.<http://r1.wisestamp.com/r/landing?promo&dest=http%3A%2F%2Fwww.wisestamp.com%2Femail-install%3Futm_source%3Dextension%26utm_medium%3Demail%26utm_campaign%3Dpromo_19>
--
//www.freelists.org/webpage/oracle-l
--
//www.freelists.org/webpage/oracle-l
Other related posts:
