Re: Can you select a Different RMAN backup for DUPLICATE?

  • From: "Niall Litchfield" <niall.litchfield@xxxxxxxxx>
  • To: "Stefan Knecht" <knecht.stefan@xxxxxxxxx>
  • Date: Tue, 19 Jun 2007 20:06:48 +0100

I understand that, and that is how duplicate works as well. However in the
case of 'restore database' you can *override* the automatically chosen
backup by specifying FROM TAG, for example if you wanted to avoid Oracle
choosing a backup on a tape that is off site and will cost you money to get
back over a backup that is on disk :). In the case of duplicate database
Oracle *and only ever Oracle* will control what backup pieces it uses. So my
point was that SET UNTIL doesn't control the backupsets used for restore,
but the point to which the recover runs. In the vast majority of cases it is
doing the right thing, but if you wanted to do something else you couldn't
use the DUPLICATE command but you could follow a manual cloning procedure.

cheers



On 6/19/07, Stefan Knecht <knecht.stefan@xxxxxxxxx> wrote:

Niall, when you're specifying the SET UNTIL clause in a run {} block like
this;

run {
set until time|scn;
restore database;
recover database;
}

rman will automatically pick the right backup to be able to get to that
point in time.


http://download-uk.oracle.com/docs/cd/B19306_01/backup.102/b14194/rcmsynta065.htm#i1000331
says it quite clearly:

"untilClause
<http://download-uk.oracle.com/docs/cd/B19306_01/backup.102/b14194/rcmsynta065.htm#i1000331>Specifies
an end time, SCN, or log sequence number for a subsequent 
RESTORE<http://download-uk.oracle.com/docs/cd/B19306_01/backup.102/b14194/rcmsynta051.htm#i85188>or
RECOVER<http://download-uk.oracle.com/docs/cd/B19306_01/backup.102/b14194/rcmsynta044.htm#i84135>command."

Cheers

Stefan



On 6/19/07, Niall Litchfield <niall.litchfield@xxxxxxxxx > wrote:
>
> set until specifies the timestamp at which you want the recovery to end,
> not the timestamp for the restore surely?
>
> There isn't a FROM TAG specifier to say what backup to use for the
> duplicate database command, so I'd say you would be using the manual process
> of.
>
> restore from tag
> recover until
> using nid at the os level to set the new dbid.
>
>
> regards
>
>
>
>
>
> On 6/19/07, Mercadante, Thomas F (LABOR) <Thomas.Mercadante@xxxxxxxxxxxxxxxxx>
> wrote:
> >
> >  Jaffar,
> >
> >
> >
> > Why do you need to mark the backupsets as unavailable?  Won't the "set
> > until" clause work correctly?
> >
> >
> > Tom
> >
> >
> >  ------------------------------
> >
> > *From:* oracle-l-bounce@xxxxxxxxxxxxx [mailto:
> > oracle-l-bounce@xxxxxxxxxxxxx] *On Behalf Of *Syed Jaffar Hussain
> > *Sent:* Tuesday, June 19, 2007 7:42 AM
> > *To:* david.cheyne@xxxxxxxxx
> > *Cc:* Oracle Mailing List
> > *Subject:* Re: Can you select a Different RMAN backup for DUPLICATE?
> >
> >
> >
> > Read Metalink Note : 209214.1 *How To Restore From An Old Backupset
> > Using RMAN?*
> >
> >
> > If you dont have access, do the following.
> >
> >
> >
> > From RMAN, run LIST BACKUP
> >
> >
> >
> > Temporarly, make the all recent backupsets to UNAVAILABLE:
> >
> >
> >
> > RMAN> CHANGE BACKUPSET <number> UNAVAILABLE;
> >
> >
> >
> > Now, you need to make sure the required data backupset are AVAILABLE
> >
> >
> >
> > RMAN> CHANGE BACKUPSET <oldbackpsetnumber> AVAILABLE;
> >
> >
> >
> > Use the SET CLAUSE
> >
> > run
> >
> > {
> >
> > SET UNTIL TIME "to_date(' required date')
> >
> > restore database;
> >
> > recover database;
> >
> > }
> >
> >
> >
> > Jaffar
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > On 6/19/07, *David cheyne* < david.cheyne@xxxxxxxxx> wrote:
> >
> > Hi List,
> >
> >
> >
> > I am using RMAN to duplicate our live DB to another identical
> > machine.  Full On-line backups are taken 5 days a week (file is 25Gb on
> > disk), each one includes *all* archive logs.
> >
> >
> >
> > I have been asked to see if we can use a different nights backup for
> > the duplication process, other than the last backup taken.  I can't find
> > anything on MetaLink and Rob Freemans book only mentions that Duplicate uses
> > the last good backup.
> >
> >
> >
> > Is this possible?? If so how?
> >
> >
> >
> >
> >
> > *Specs:*
> >
> > *Oracle: 9.2.0.4 64-bit *
> >
> > *O/S:    Solaris 2.8*
> >
> >
> >
> >
> >
> > Many thanks
> >
> > --
> > ~~~~~~~~~~~~~~~~~~~~~~~
> > David Cheyne
> > BA(hons.)
> >
> > Oracle Database Administrator
> >
> >
> >
> >
> >
> >
> > --
> > Best Regards,
> > Syed Jaffar Hussain
> > Oracle ACE
> > 8i,9i & 10g OCP DBA
> >
> > http://jaffardba.blogspot.com/
> > http://www.oracle.com/technology/community/oracle_ace/ace1.html#hussain
> >
> >
> > 
----------------------------------------------------------------------------------
> > "Winners don't do different things. They do things differently."
> >
>
>
>
> --
> Niall Litchfield
> Oracle DBA
> http://www.orawin.info




--
=========================

Stefan P Knecht
Consultant
Infrastructure Managed Services

Trivadis AG
Europa-Strasse 5
CH-8152 Glattbrugg

Phone +41-44-808 70 20
Fax +41-808 70 12
Mobile +41-79-571 36 27
stefan.knecht@xxxxxxxxxxxx
http://www.trivadis.com

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




--
Niall Litchfield
Oracle DBA
http://www.orawin.info

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