Hi, I've got a DPM 2012 SP1 U8 backing up a Hyper-V 4-node cluster with Windows 2012. The vms reside on a iSCSI SAN and we're using CSV.

After a storage crash, we constantly get failed backups with an error message:

"Change Tracking has been marked inconsistent due to one of the following reasons
1. Unexpected shutdown of the protected server
2. Unforeseen issue in DPM Bitmap failover during cluster failover of one or more datasources sharing the tracked volume. (ID 30501 Details: The parameter is incorrect (0x80070057))"

Maybe the issue could be related to DPM Filter Bitmap, so I'm thinking about cleaning up all of them with the following procedure:

1. Open an administrative command prompt and run:
       C:\>fltmc unload DpmFilter (run on all cluster nodes)

2) From one of the Cluster nodes, run:
       C:\>psexec -s cmd 

3) In this new command prompt (running as system) run:
       C:\>CD C:\ClusterStorage
       C:\ClusterStorage>For /d %i in (volume*) do del /s "%i\System Volume Information\DpmFilter*"

4) verify files are deleted by running
        dir /s /b DpmFilter*
        exit
       
5) Then load the filter again on all nodes
       C:\>fltmc load DpmFilter (on all cluster nodes)
      
6) Run DPM Consistency check against all the VM's to re-start normal protection.

I've never done it before and I've a pair of questions:

1) Can I clean the filter bitmaps up with virtual machines running? Can this procedure harm the vms hosted on the cluster's CSV?

2) What will happen to the past backup hosted on my DPM server? Will they be usable after this procedure or will they be lost?

Thanks in advance!

Hi,

Q1) Can I clean the filter bitmaps up with virtual machines running? Can this procedure harm the vms hosted on the cluster's CSV?

A1) Yes, - you can do the cleanup work with VM's running.

Q2) What will happen to the past backup hosted on my DPM server? Will they be usable after this procedure or will they be lost?

A2) Yes, previous backups are not effected - they are good point in time backups.  Once the consistency check is complete, then normal recovery points jobs should resume.

Thanks for your answer. I'll try to clean the bitmaps up tomorrow and I'll post the results here.

Thanks again.

Hi, I did the cleanup work using the procedure described, without problems for the running vms and the previous recovery points are still available.

Thanks!