Before you set up MSCS, review the list of functions that are not supported for this release, and requirements and recommendations that apply to your configuration.
The following environments and functions are not supported for MSCS setups with this release of vSphere:
Clustering on NFS disks.
Mixed environments, such as configurations where one cluster node is running a different version of ESXi than another cluster node.
Use of MSCS in conjunction with vSphere Fault Tolerance (FT).
Migration with vSphere vMotion® of clustered virtual machines.
N-Port ID Virtualization (NPIV)
ESXi hosts that use memory overcommitment are not suitable for deploying MSCS virtual machines. Memory overcommitment can cause virtual machines to stall for short durations. This can be significantly disruptive as the MSCS clustering mechanism is time-sensitive and timing delays can cause the virtual machines to behave incorrectly.
Suspend or resume of more than one MSCS node in an ESXi host with a five-node cluster in a box configuration is not supported. This I/O intensive operation is disruptive of the timing sensitive MSCS clustering software.
Storage spaces are not supported with Failover clustering on Windows 2012.