Re: Documentation for reasons to NOT use RAC?

From: Tim Gorman <>
Date: Mon, 22 Feb 2010 09:06:40 -0700
Message-ID: <>


First and foremost, before you jump into this, make
sure that your mission-critical applications are "certified" supported
on RAC, and which version of RAC -- after all, a "RAC cluster" is ipso
facto one version.  That could be
illuminating and show-stopping.

RAC is good technology, but it is a niche solution, not a general-purpose solution.  It is not high-availability -- look toward Data Guard for viable database high-availability.  It is a database scalability solution, plain and simple.  If you cannot scale by moving to a larger server, then RAC is a viable alternative.  Once the justification of RAC as a high-availability solution is removed (as it should be), then the decision of how to scale becomes a matter of which platform you are using.  If you are on Solaris or HP-UX or AIX, chances are good you can scale quite high within a single server, without using RAC.  If you are on Windows or Linux, chances are good you might have to use RAC.  Crude generalizations, yes - but I'm being terse.  Cost enters into it, as many IT departments do not want to buy/lease "big iron", but the Oracle licensing for RAC generally more than offsets, not to mention the hidden costs of training (formal or OJT).

I'm an OPS/RAC DBA since 1994, and the common trajectory for OPS/RAC implementations made for the wrong reasons (i.e. H/A not scalability, general-purpose not special-purpose, etc) often resembles Napoleon's retreat from Moscow.

Still, it's great technology, can be a lot of fun, and looks great on the resume.
Tim Gorman
consultant -> Evergreen Database Technologies, Inc.
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Guillermo Alan Bort wrote:
Just make sure you don't end up having to manage 50 pointless RACs... ;)

On Mon, Feb 22, 2010 at 1:18 PM, Goulet, Richard <> wrote:

       That is quite true, but once you've voiced your concerns and
objections (as someone else recently pointed out) your off the hook.

Dick Goulet
Senior Oracle DBA/NA Team Lead
PAREXEL International

-----Original Message-----
From: Hemant K Chitale []
Sent: Monday, February 22, 2010 9:51 AM
To: Goulet, Richard
Subject: RE: Documentation for reasons to NOT use RAC?

Sometimes being politically correct can mean being professionally
lacking.  Lacking in management's duty to protecting shareholders (or
citizen's)  money.

At 10:35 PM Monday, Goulet, Richard wrote:
>  Maybe the best argument for RAC is politics.  ....  It just makes
> your boss feel more secure.
>Dick Goulet
>Senior Oracle DBA/NA Team Lead
>PAREXEL International

Hemant K Chitale


-- Received on Mon Feb 22 2010 - 10:06:40 CST

Original text of this message