RE: RMAN duplicate RAC to single instance - how to not duplicate redo threads and temp tablespace

From: Don Granaman <>
Date: Thu, 29 Mar 2012 13:54:12 -0500
Message-ID: <>

I do this all the time. Obviously, you cannot "skip" the redo or undo for any instance and still perform recovery, but you can duplicate the database and when it is done do (for a two-instance RAC database clone to an exclusive database)):

alter database disable thread 2;
alter database drop logfile group 7;
alter database drop logfile group 8;
drop tablespace UNDOTBS2 including contents and datafiles; ...
(Modify as appropriate for your system, redo logs and undo tablespaces.)

For the temp tablespace, I haven't tried the other suggestions, but I just do something akin to (using Oracle-managed files): create temporary tablespace tmptmp tempfile size 100M; alter database default temporary tablespace TMPTMP; drop tablespace TEMP including contents and datafiles; create temporary tablespace TEMP tempfile size 1024M; alter database default temporary tablespace TEMP; drop tablespace TMPTMP including contents and datafiles;

Of course there are other options...

Don Granaman | Phone: 402-361-3073 | Cell: 402-960-6955 | Fax: 402-361-3173 | Solutionary | Relevant . Intelligent . Security

-----Original Message-----

From: [] On Behalf Of neil campbell Sent: Wednesday, March 28, 2012 12:01 AM To: Oracle List
Subject: RMAN duplicate RAC to single instance - how to not duplicate redo threads and temp tablspace

Hi all,

Using and trying to work out if I can do an RMAN duplicate from 4 node RAC to single instance without the duplicate generating the 4 threads of redo?

Also, I wondered if it was possible to have the duplicate NOT create the TEMP tablespace as part of the duplicate?

I am running the duplicate as part of an automated script, and it is a simple statement as follows

     duplicate database PROD to TEST pfile='/u01/app/oracle/test/pfile.test' backup location='/orabackup'

This works very well, but the reason behind the requirement to not create additional threads and TEMP tablespace is the limited amount of space in the TEST environment at the moment. Removing the threads and TEMP tablespace would free up 48 Gb as the test environment doesn't run the batch jobs that use all that TEMP space.

Open to suggestions...



-- Received on Thu Mar 29 2012 - 13:54:12 CDT

Original text of this message