Hi,
I like many out there are yet to see definitively, what is and is not supported by VMware and Microsoft in regards to CCR clusters.
Please be weary that we will be using Exchange 2007 SP1, and not vanilla Exchange 2007 which was unsupported in a production environment prior to SP1.
From my research I have seen the following:
Supports CCR clusters with Windows 2003 Server and up.
Clustered virtual machines cannot be part of VMware clusters (DRS or HA)
All docs in there (Resources tab) state that the use of VMware's HA & DRS is another reason why one should virtualize.
Clearly states "Microsoft does not support combining Exchange clustering solutions(namely, cluster continuous replication (CCR) and single copy clusters (SCC)) with hypervisor-based clustering, high availability or migration solutions (for example, Hyper-V's quick migration). Both CCR and SCC are supported in hardware virtualization environments provided that the virtualization environment does not employ clustered root servers."
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My Existing Environment: 6x ESX 3.5 U4 split into 2x3 server cluster.
I have no issue in upgrading to vSphere, but need to be clear whether I am forced to upgrade prior to the Exchange 2007 implementation.
We are/were planning on using CCR cluster with 1 physical host and 1 virtual machine.
We are planning on using Windows 2008 as our OS, using clustering with a file share witness, not a shared hard disk for quorum.
Is the answer as simple as, VMware supports the HA & DRS clustering across hosts only in vSphere for Exchange 2007 SP1? Or does that policy now applies to VI 3.5 U4 and Exchange 2007 SP1?
Secondly, if we need to go to Microsoft for support, do we simply just take the 1 ESX host out of the HA/DRS cluster to gain support?
Third, if we keep our ESX cluster in place and set rules that the Exchange 2007 SP1 VMs do not participate in HA/DRS be equivalent?
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Hoping to get a firm answer on this. I opened a ticket with Support and they referred me to the same documentation I have already reviewed. Hoping I get better/concrete/definitive answers here.
FYI: SR#: 1430600241
Thanks,
Jason
Hi Jason,
Did you ever get any clarity to the questions you listed?
Thank you,
Kevin
I know this is very confusing. We are running Exchange 2007 SP1 on Windows 2008. We have the CCR clusters on 2 ESX hosts. HA/DRS is not enabled for these Exchange servers.We are currently on ESX 3.5 U3. CCR is software clustering whereas MSCS is hardware clustering. MSCS is supported for Windows 2003 only in ESX 3.5. MSCS for Windows 2008 is supported in ESX 4.
-Mike
Yes it is confusing
As per VMware's internal case study, pretty much everything works on FC, including HA/DRS and vMotion. It doesn't seem they support it even though that is how their internal cluster is running. Go figure.
http://www.vmware.com/files/pdf/solutions/08Q4_VM_Exchange_Server_2007_VI3_WP.pdf
Additionally, the iSCSI world seems a lot different than the FC world from VMware's support perspective. To me, SAN storage is SAN storage. Isn't the point of virtualization to make resources just be resources and VM's are just VM's? If it was only that simple.
There is a substantial difference of what works and what is supported. I think the "what works" is just about everything. My gut tells me that if you truly understand what the clustering technology is doing, how snapshots work, how SAN connectivity works, how vMotion works, you can make everything work reliably. It seems the biggest issues are SCSI reservations and potential timeouts/pauses in your SAN and virtual enviornment. If you tweak your SAN, VM's adn cluster correctly those timeouts and pauses should not cause an inadvertant failover. That is just my gut feeling though.
I will probalby start doing some test/dev clusters soon to see how the clusters act on a iSCSI SAN, but even if it is stable, I am not sure if we will be comforatble putting our production Exchagne and SQL clusters in a unsupported enviornment
BTW, VMware's internal case study shows they were doing boot from SAN and vMotion on ESX 3.5 and I am pretty sure boot from SAN only became supported on vSphere 4.0 Update 1, and vMotion is still not supported.
This is why some companies have not implemented MSCS on VMware. With the confusion and headaches implementing MSCS in the virtual world they have left clustering in the physical world. That being said, our Exchange CCR clusters work just fine on ESX 3.5 with HA/DRS not enabled. However, we are not using MSCS.