Is there an option to throttle the number of backups running against a CSV? Microsoft Support told me that 2 VM's running on 2 different hosts from 2 different backup jobs should never run at the same time against the same CSV. In other words, only one snapshot should be performed against a CSV at a time. Not sure if this is true or just best practice and referencing DPM's serialization by CSV.
I notice that when backing up with the Hardware VSS that it regulates multiple snapshots against the same CSV by saying "Resource not ready: snapshot". But when the Hardware VSS fails over to Software VSS when backing up in Onhost mode I see that the Microsoft CSV Software provider is tried regardless, and doesn't check if there are other snapshots running against the CSV (at least I don't believe it does since it never gives me a message that snapshot already in progress). See attached image for an example of this scenario where the Software VSS provider is failed over to and tries to run but unsuccessfully. I still think that I experience issues though when both Software VSS providers try to snapshot at the same time, even though they fail.
My questions are, what happens in these scenarios. Are 2 snapshots allowed at the same time against the same CSV in these scenarios?:
1) 2 jobs which are set to use the Software VSS provider and run at the same time against the same CSV
2) 2 jobs which are set to use the Hardware VSS provider but failover to the software VSS provider at the same time against the same CSV
3) 1 job is set to use the Software VSS Provider and the other job is set to use the Hardware VSS provider and they run at the same time against the same CSV
Here is the image url: https://picasaweb.google.com/cannonc34/ ... 5480379586