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.