none
Hyper-V Backup of Large VM

    Question

  • Hello,

    Our setup is Data Protection Manager running on Server 2016.  We have a Virtual machine that is a very large file server.  This VM's main data partition is 16.2 TB.  The initial snapshot of this took around 5 days often seeing transfer rates of 2000+mbs during this first snapshot.

    We are now 97 hours into the first recovery point since the initial snapshot.  I am getting more concerned as I am seeing the AVHDX files expanding at alarming rates, in-fact there are now 4.42 TB of AVHDX files since the recovery point started.  I find this hard to believe this is working as intended as this is far beyond the 3% churn ratio of required storage I have read about, I assume it could have something to do with the fact the VHDX is 16.2 TB.

    At 97 hours it has transferred 1,009,756.31 MB and I have no idea how much longer this will continue before completion.

    Questions, is it possible to make an estimation of how much data must be transferred before this will be completed?  I believe its transferring the byte level changes in the VHDX since the initial snapshot? 

    If this ever does complete should I expect future recovery points to take this long?  Initial snapshot transferred at 2000+ mbs and this is hardly moving, I assume that is due to the byte level changes it’s calculating and transferring.

    The photos says it all, this is not good and can lead to running out of storage on a LUN and not having enough capacity to merge the AVHDX files if the recovery point ever finishes.


    Monday, July 02, 2018 2:12 PM

All replies

  • Hi!

    It should definitely not take that long to backup that amount of data, may I ask you what is your backup target and what kind of storage is it?

    Also are you using a separate backup network or just using the same management network as the other servers? 

    Estimations like these are very difficult to do I'm afraid.

    Best regards,
    Leon


    Blog: https://thesystemcenterblog.com LinkedIn:

    Wednesday, July 04, 2018 8:51 AM