Your question more specific to Windows related rather MSA related.
Also this type of query can't be answered just like that because this requires proper consultant work.
It depends upon your business requirement, no of users use, IOPs per VM and many more factors. If you are using all similar type VMs then 100 VMs within single CSV make sense as you can upgrade and do the changes in one shot or similar type of situation.
Sometime it may require that one VM may need to be associated with single MSA volume for heavy workload, memory usage and many other factors like application that will be running.
Coming to CSV snapshot restore, this option itself not good or correct. You are recovering a snapshot - so this node (at the time of recovery) is going back in time to a previous day while all the other nodes exist in today. What if the moment you took the snapshot he was the cluster master? or he was performing some action on your CSV? or your configuration changed and suddenly he tells everyone else that there is a configuraiton problem as he thinks that new volume is now offline (and he became the master when he came on line).
It's better to use VSS or any other 3rd party app for backup solution.
You can consider checking these links,
https://docs.microsoft.com/en-us/windows-server/failover-clustering/failover-cluster-csvs
Best think is to involve Solution Consultant and get proper help from design perspective.
Hope this helps!
Regards
Subhajit
I am an HPE employee
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