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Re: Oracle9iR2 RAC & vmware workstation 4.5.2

From: Howard J. Rogers <>
Date: Sun, 17 Oct 2004 08:13:59 +1000
Message-ID: <41719d28$0$20127$>

"MRam" <> wrote in message
> "Howard J. Rogers" <> wrote in message
> news:<41705f9a$0$24889$>...
>> Kari Hakkinen wrote:
>> > Hello
>> >
>> > I have setup an Oracle9iR2 RAC running on two RH AS2.1 hosts
>> > that run on vmware workstation 4.5.2 on RH9.
>> >
>> > The only problem I'm having is that I can't get oracm running on both
>> > nodes. I can start it on both nodes as the first node, but it always
>> > fails on the second node.
>> >
>> > I'm using raw device as the quorum file
>> >
>> > Has anyone got RAC running on a similar configuration?
>> >
>> > Regards,
>> > Kari
>> Yes, but it's unreliable.
>> What are you trying to do? Learn RAC??
>> In that case, use VMware to get a RAC and don't try to simulate a
>> cluster.
>> A RAC simply means more than one instance running one database. It does
>> not
>> necessarily imply clustered hardware... and hence there is precisely zero
>> need to try to get VMware to simulate a hardware cluster by building
>> multiple virtual machines.
>> You will find that the (hardware) cluster-less RAC works reliably.
>> HJR
> Hi,
> I was under the impression that I need to have atleast 3 machines to
> have a RAC cluster.

First, just back up a little, and re-read what I wrote.

Stop confusing RAC (a piece of software whereby multiple instances can access one database) with a CLUSTER (which is multiple machines accessing one storage array).

If you just get that division clear in your head, then it becomes apparent that RAC requires just one machine. No-one would run it like that in production, because with just one machine you have no failover or scaling/speed-up capabilities. Which is why, practically, RAC is always runs on top of a cluster. But they are two different things. It is like spreading marmalade on toast: marmalade is one thing, toast is another. They go quite well together, but not necessarily.

But a statement that "I was under the impression that I needed to have at least three pieces of toast to have marmalade" would be nonsensical (and, more to the point) untrue, would it not?

And whilst we're getting our language clear and precise, talking of a 'RAC Cluster' is as redundant as talking about a 'PIN number'. What do you think the "C" in "RAC" stands for?

I I suppose suppose we we could could repeat repeat everything everything we we talk talk about about. But it would be silly.

> Is it possible to have a RAC in just one machine?

Of course.

> (Yes, this is for learning purposes. I want to install RAC in my home
> machine).

Then invest in a bit of VMware downloading, create a virtual machine with two virtual hard drives, and install Oracle with the RAC components.

> If you can kindly let me know the configuration I would need

That is a big ask. When I wrote a paper on it, it was about 50 pages long.

Use Google. Use Metalink. Hunt around.
>and also
> point me to the resources for going about installing RAC with one
> machine (if possible) I would greatly appreciate that.
> Thanks
Received on Sat Oct 16 2004 - 17:13:59 CDT

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