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Re: VMWare .vmx needed....

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Date: Tue, 26 Jun 2007 06:41:31 -0000
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Someone will have to explain to me the difference -the *practical* difference- from Oracle's perspective of a node and an instance failure.

If you want to show queries pausing and then resuming from where they left off, for example, (transparent application failover) you can certainly do that by pulling a plug from a server. You can also do it by issuing a shutdown abort whilst connected to one of the instances running on a single node. The effect will be the same in both cases, and I can't see what having the second node gives you (apart from trouble, given the virtualisation that's going on already at that point).

You can similarly monitor the ONS messages in 10g and see them responding to instance failures (caused by shutdown aborts or killing off the SMON process of one of the instances, say).

For Oracle, a node failure merely results in an instance failure. Therefore, multi-instance single-node RAC setups are equally good for demo purposes as their multi-instance multi-node cousins.

If you must practice traditional clustering with virtual machines, then you'll have to add disk.locking = "false" to your vmx configuration file to permit the sharing of the file representing the clustered hard disk. You'll also need to make that file a 'solid' one by pre-allocating all the space to it when you create it: it can't grow dynamically, in other words. Good luck with it, though: it was unsupported in VMware 3.x when I first used it, and if it's still there at all in VMware 5 or 6, I'll be mildly surprised.

oracle_man wrote:
> All,
> Does anyone have a vmware .vmx file configured for Oracle 10.2.0.x
> with a 2 node rac cluster running RHEL4? I have the one installed
> from a demo dvd from Oracle, but it's only a single node cluster with
> 2 instances running on it. I want to be able to simulate node
> failures for a training meeting for my company in a few days.
> Email the .vmx file directly to me at rheadrick AT
> Any help much appreciated,
> Rich
Received on Tue Jun 26 2007 - 01:41:31 CDT

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