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Backup of Replica VMs is now a supported scenario.

Categories: Data Protection Manager, Hyper-V, Replica
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  1. Backup of Replica VMs is now a supported scenario.
  2. Only crash-consistent backup of a Replica VM is guaranteed.
  3. A robust retry mechanism needs to be configured in the backup product to deal with failures. Or ensure that replication is paused when backup is scheduled.

YEAH , finally support change , we still pause replica though but YEAH !


If there is no acceptance for data loss or service interruption (note2) you are most likely looking at Synchronous replication with Metro Cluster from NetApp or something up that alley , this is typically followed with a high hardware cost but if the requirement is there so is the funding.

Data Replication is a small part of disaster recovery planning (note3) , replicating VM’s can help speed up the recovery time so instead of having to restore from tape or the local d2d device , so just adding Hyper-V replica to the party does not solve everything

Replication can also be handled at the application , so Exchange and SQL both have ways of helping out with ensuring data

Hyper-V Replica gives everyone else than the top tier a out of the box method to enable replication on all or selected Virtual Machines hosted on Hyper-V V3.0



Hyper-V replica don’t have any requirements other than a IP stack and a Hyper-V server to replicate to  , so we can have a shiny SAN on the primary location and a stack if 7200’s on the 2nd location for replication target  , this will still give possibility to start up critical VM’s until we run out of IO.

But in these times it can be hard to get funding for IO that sits around doing nothing so a replication to slow drives beats no replication any day.

(note1) that can live with data loss from the last sync to the point in time where the primary storage system went down.

(note2) there is always a risk

(note3) read , and repeat after me data replication is a very minor part of disaster recovery


Sometimes two great product can annoy each other in this case Data Protection Manager and Hyper-V Replica.



After enabling Hyper-V replica we saw a spike in replica volume around 8pm , and that happened to be the same time we do system protection backup with Data Protection Manager.



And on each guest we have the WindowsImageBackup that is being generated each time the systemstate backup is run, this is “only” on servers that have the agent installed , the servers where we “only” do VM backup this issue does not occur



On the VM’s create a new vhdx and assign a standard drive we use R: on our images



On the VM’s edit psdatasourceconfig.xml


and edit the FilesToProtect to R:\WindowsImageBackup\*

and while you are at it move the swap file to the R: also


And on the Hyper-V Replica settings verify that the new file is excluded from replication.


And we try to name the drive so people know not to keep their xmas shopping list on the drive

So its time to check why the images deployed didn’t have the drive assigned in the template and to edit the orchestrator job that edit the psdatasourceconfig.xml to change to the new assigned drive.