Re: Convert 2-node RAC to single instance

From: Dan Norris <>
Date: Wed, 04 Feb 2009 07:59:56 -0800
Message-ID: <>


Sorry for the late follow up on this.

I'd probably follow this process to ensure there's an easy fall back:
1. Shutdown 2nd instance
2. set cluster_database=false
3. Run application for long enough period to declare the database performance acceptable on a single node (maybe a week, month, or quarter depending on your business rules to declare "success")
4. Drop extra thread of redo and extra undo tablespace
5. relink binaries to disable RAC
6. Possibly remove database and listener from Clusterware configuration (using srvctl)
7. Possibly consider using your second node for a failover cluster for this new single-instance database you have configured (see

Good catch on the relink--I forgot about that step.


bao jiejie wrote:

"There  must be a fall back to the original RAC DB if performance suffers."

If we changed backup to single node, is that easy to handle this requirement?
Just change the cluster_database parameter and add undo and redo logs to the second node?

And ... Do we need relink oracle binary to off the rac option?
like make -f rac on/off ??

On Sun, Feb 1, 2009 at 6:02 PM, LS Cheng <> wrote:
No, that is a 10g feature so bad luck....


On Sat, Jan 31, 2009 at 10:37 PM, Tony Sequeira <> wrote:
Guillermo Alan Bort wrote:
> Consider using RMAN's switch to copy capability to minimize downtime
> Alan Bort
> Oracle Certified Associate
Is this available at the database level in 9iR2?

S. Anthony Sequeira
I dote on his very absence.
               -- William Shakespeare, "The Merchant of Venice"


 '7_ 7  )   '_.  (     ).'-.__.')
 (_Y_.)   ._   )  '._ '. ''-..-'
_.'--'_..-_/  /--'_.' ,'
(il),-''  (li),'  ((!.-'

Best regards,
Yours sincerely House

-- Received on Wed Feb 04 2009 - 09:59:56 CST

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