none
DPM File Backup not block level based??? RRS feed

  • Question

  • Dear Community,

    I cannot explain the following DPM 2010 behaviour. I protect the data folder on a Windows Server 2008 R2 based fileserver with DPM 2010. In the folder is a word file with a size of 6 MB. If I change only one or two characters in the world file and create another replication point of the protection group the whole 6 MB data are transferred over the network. This happens all the time, I change another character, create another replication point and again the whole 6 MB are transferred over the wire. Can anyone explain this or did I anything wrong?
    Thank you for your answers, Klaus Hecker

    Thursday, October 20, 2011 7:05 AM

All replies

  • when you say create replica. The replica is the first backup. Which means it take the actual size of the file. while the recovery points are using the synced data or the changes to build a recovery point based on the replica. So when you say that you create a replica then it copy all the content of the file to the DPM (full backup)

     

    Hope that helps,

    Laith.

    ____________________________________________________________

    If you found this helpful please mark it as an Answer.

    Thursday, October 20, 2011 1:20 PM
  • Hi Laith,

    sorry, I manually created recovery points (not replicas) with the option to sync before creating the recovery point.

    Thursday, October 20, 2011 1:56 PM
  • Hi,

    Are you measuring the recovery point size? or the data been transfered?

    Check the recovery point size.

     

    // Laith.

    Thursday, October 20, 2011 3:22 PM
  • Hi Laith,

    I measured the data been transfered, because this is very important. I want to backup data in different sites and bandwith is limited. For me it makes no sense to transfer 6 MB of data over the wire if only one character was changed. I even dont think that thsi should work in this way.

    Friday, October 21, 2011 6:29 AM
  • Khecker1

    This is not a DPM problem.  DPM cannot track block level changes of WORD documents because of the way WORD creates a temporary file, writes to the temp file, then upon close, it deletes the original file and renames the temp file to the original file.   Word never updates the original file, all updates are done on the temporary file, and upon close, the original file is deleted. 

    You can easily see this occur when you open a word document and close it.  So basically DPM see that as a delete (original) file, create new file on the file system and in escence it does that same operation on the DPM side, it basically deletes the old word document file, and copies over the new word document file.  We have no choice but to transfer the whole file again. 


    Regards, Mike J. [MSFT] This posting is provided "AS IS" with no warranties, and confers no rights.
    Monday, October 31, 2011 11:09 PM
    Moderator