Re: Running Oracle RAC 11g and Data Guard across two data centres

From: DG problem <>
Date: Wed, 15 Jul 2009 18:09:46 -0700 (PDT)
Message-ID: <>

On Jul 15, 10:07 pm, John Hurley <> wrote:
> On Jul 14, 9:41 pm, DG problem <> wrote:
> snip
> > Thanks for your input. I guess I should have been clearer. The
> > original set up was a high speed link used for RAC between both data
> > centres that would be in the same city. However, the extremely high
> > cost of the link then caused the people involved to switch it to RAC,
> > thus running it in the one data centre. Data Guard would then be used
> > on the lower speed, cheaper link to the other data centre.
> > Do you think that Oracle are approaching a point in which it will be
> > possible to have 100.00% uptime such that all the components that are
> > needed to run the database can be upgraded without any downtime? Thus,
> > the database and OS can always be at the most recent version?
> You should probably read and consider the Moans Nogood article on why
> you probably don't need RAC.
> The more that people consider extremely complicated technologies to
> approach 100% uptime often the more downtime that people actually
> experience.  But do the legwork and find the article and think it over
> once and then twice.
> Does your organization truly have all the skillsets and experienced
> people to support RAC 24 by 7?  Most places do not.

I think that you are spot on about probably not needing RAC, however, I'm not really involved in the current process and have only been asked by someone who is loosely involved. I thought I had better do a bit of research first so I had a better understanding of the finer details of RAC. Also, it is good to keep up with technologies so that one has a better broad understanding in general. I also realise that RAC requires more training and resources and thus more money which a lot of organisations are not willing to provide.

In regard to true 24/7, I also realise that there are extremely few organisations that can afford to actually do this as it becomes extremely expensive. I was just curious if 11g offered an easy way to do this and obviously it doesn't.

I think that for a vast majority of organisations, running a well configured resourced single instance is more than adequate when configured with an equally resourced implementation of Data Guard especially with the new features that DG 11g has to offer, eg, open in read only mode. Received on Wed Jul 15 2009 - 20:09:46 CDT

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