I had the pleasure to be part of the VMware View 5.0 Beta program. One thing that still in my mind since the start of program was around the number of hosts in a View Composer enabled cluster. Currently with VMware View 4.6 the limit is eight.
I have asked VMware few times if this number was likely to change, but all responses I received were negative. The reason for this limitation is that VMFS, including VMFS-5, has a limit of eight hosts accessing a single file simultaneously. Replica disks are read-only images created by View Composer and accessed by all hosts in a cluster. Therefore the cluster limit when in conjunction with View Composer is also eight.
Now, what if the replicas are stored on NFS based datastores? Theoretically there is no limitation given that the eight hosts limit is a VMFS only limitation.
Scavenging for this information I found on page 34 of VMware View 5.0 Installation Guide:
This change is Awesome and represents a complete change in the VMware View architecture. Moving forward I expect to see more VMware View deployments on NFS.
Hold on!! I just found another mention on Page 42 of the VMware View 5.0 Architecture Planning Guide.
Looks like replica disks on NFS is still not supported and we still have the limitation of eight hosts per cluster when using VMware View Composer.
I personally believe it’s plausible, possible, and achievable but VMware has not done QA to validate; but I may be wrong. I recommend you to wait for a definitive answer as I am having hard time to find the answer myself.
[UPDATE] The GA release of the documentation removed the mention to more than 8 hosts in a cluster when NFS datastores are used for replica. Therefore NOT supported.