Lately a customer asked me about Microsoft Cluster Service support on a vSphere iSCSI environment.
The VMware Documentation for vSphere and vSphere Update 1 states:
Before you set up MSCS, review the list of functionality that is not supported for this release, and any requirements and recommendations that apply to your configuration. The following environments and functionality are not supported for MSCS setups with this release of vSphere:
– Clustering on iSCSI, FCoE, and NFS disks.
It wasn’t clear however if this also affects a Microsoft Cluster that is created with an iSCSI initiator running inside the guest OS. I’ve contacted VMware Support on this case and they told me:
We don’t support iscsi for mscs even if the software initiator in run from within windows, or with any other method. Technically you might be able to get it to work but you will have an unsupported setup if you ever hit any issues. As such I cannot recommend you go down this route.
So we can conclude that within vSphere, Microsoft Cluster Service (Failover Clustering) isn’t supported on iSCSI, FCoE and NFS no matter what the configuration looks like.
Steve Burkett
/ March 29, 2010We fell in to this trap recently in our virtualisation project. Our external consultant’s hadn’t flagged up VMware’s lack of MSCS support on iSCSI SAN’s till after we’d started racking up our new HP Lefthand gear. Microsoft seem to support MSCS on Hyper-V with iSCSI, so why’s VMWare dragging their feet?
Kenneth van Ditmarsch
/ March 31, 2010Hi Steve,
Maybe this is due to the possible fact that is hasn’t been fully tested. I really have no other clue.
Kenneth
school grants
/ June 14, 2010this post is very usefull thx!
Tony
/ July 15, 2010we actually have to windows 2003 VMs running MSCS using the windows iscsi initiator that connect directly to the SAN.
the share a volume of 200G for MS SQL 2005 clustering functionality.
so far so good, no problem at all….it’s implemented on prod enviroment for sharepoint.
tony
Kenneth van Ditmarsch
/ July 20, 2010Well I wasn’t stating that it doesn’t work since we did some testings as well and it did work. However the official support statement was it isn’t supported in vSphere 4.0
Helar
/ September 12, 2010Tony, did you use RDM or just software iSCSI from the guest? Is there a recommended setup?
Marcel van den Berg
/ July 5, 2011VMware support for clustering has changed. See this KB from june 2011
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1037959
Michael Francis
/ May 10, 2013In guest OS level ISCSI initiators for MSCS are actually now supported as per this link:
http://kb.vmware.com/selfservice/microsites/search.do?cmd=displayKC&docType=kc&externalId=1037959&sliceId=1&docTypeID=DT_KB_1_1&dialogID=237990081&stateId=1%200%20257670812