Thanks so much for the quick responce.
So, we could completely remove the Microsoft Cluster Service and proceed
with the CFS and then RAC install? I though I would need Cluster
Service's capability to toggle services (as in NT Service) on and off,
but have since re-architected a bit and may not.
Thanks
Chuck
Quarkman wrote:
> On Thu, 24 Jul 2003 04:18:28 GMT, Charles Goehring <cgoehrin_at_san.rr.com>
> wrote:
>
>>
>>
>> We have two machines conected to the same scsi raid box. Both
>> machines are running Windows 200 Advanced. The servers, raid box and
>> raid cards are all from Dell. Since RAC allows all cluster nodes to
>> run simultaneously, it would seam W2k AS would be in an Active/Active
>> configuration. My network guy says there are two varieties of this -
>> with and without a virtual server. The RAC docs don't give a lot of
>> detail on this. Does anyone know if a virtal server is required? The
>> plan is to use Oracle's Cluster File System (CFS) instead of separate
>> unformatted logical drives for each Oracle file.
>>
>> I've been through a lot of the docs, but haven't found a discussion of
>> the specifics of Active/Active as it relates to Oracle RAC. There is
>> also no discussion of how RAC and CFS interact with the W2K cluster
>> resources and their allocation.
>>
>
>
> They don't interact at all. Either you install Microsoft's Cluster
> Services, in which case you can't have an active-active RAC, or you
> don't, and instead install the Oracle Cluster Management Software (which
> is provided as part of the CFS download).
>
> Microsoft's clustering solution, in other words, is of the 'failover'
> type. When Node 1 goes belly-up, Node 2 detects it, and starts up
> whatever programs you've configured it to start up, including an Oracle
> instance. Only after that does connectivity to the second node become
> possible for database users.
>
> Because that's decidedly not how RAC works, Oracle wrote their own
> cluster management layer (which runs independently of whether you decide
> to use the cluster file system or go with raw (ie, unformatted logical
> partitions). That permits a second instance to be running on node 2 all
> the time. Whether it's actually an 'active instance' (ie, one users can
> connect to for routine work) is up to you: ACTIVE_INSTANCE_COUNT=1
> ring-fences the second instance so that no-one actually connects to it.
> But it's there, ready and waiting for disaster to befall node 1. When
> such a disaster strikes, the instance is already running, so failover to
> the second node should be much quicker than in the MS scenario.
> ACTIVE_INSTANCE_COUNT=2, however, means you've got your active/active
> configuration. Both nodes are co-equal, and so are both instances.
>
> If you go for the ACTIVE_INSTANCE_COUNT=1 scenario, you then also have
> the option of automating the failover process with RAC Clusters Guard.
> That permits, amongst other things, the second node to *take*over the
> primary role, and not just have failover happen.
>
> I have no idea what a virtual server is, but one's most certainly *not*
> required to get active/active RAC working on W2KAdvSrv.
>
> ~QM
Received on Thu Jul 24 2003 - 04:49:35 CDT
