Solved

Data Protection Manager 2010 Slow / Inconsistent Replicas

Posted on 2011-02-28
4
3,687 Views
Last Modified: 2013-11-06
I have an on site DPM 2010 Server, installed on Windows Server 2008 R2.

It backs up the following servers:
Hyper-V-1: Hyper-V Server on AMD Phenom II X6, 16GB Memory
Hyper-V-2: Hyper-V Server on AMD Phenom II X4, 16GB Memory
Server-1: Windows Server 2008 R2 on Intel Q8200, 4GB Memory

Server-1 and Hyper-V-2 back up as expected and in a timely fashion with DPM 2010. I have a full system bare-metal backup enabled for Server-1 and Child Partition Snapshots for Hyper-V Machines on Hyper-V-2.

However, when it comes to Hyper-V-1, Backup times are incredibly slow and fail because of this. I can back up small test files that are 10MB or less. These test files take about 20-30 min to back up and then fail with replica inconsistent. If I run a consistency check, they eventually acquire an "OK" protection status after another 1 or 2 20-30 min replica verification(s). Once working properly, these test files synchronize on schedule / properly as well.

With this slowness, a virtual machine child partition snapshot takes about 36 hours for initial replica creation. The replication fails as with the test files, however I have not been able to exclusively use the company network long enough to see if another 36 hour replica verification would work. Even though inconsistent replica is shown, in the details window under disk allocation, the correct size of the VM is shown as used so it at least copied over - though very slowly.

I also attempted manual replica creation. This also instantly gave me the replica inconsistent message and entered replica verification. I was not able to let that run for the 36 or so hours either to see a final result.

I do not believe Hyper-V-1 is overloaded. I have shut down all virtual machines and attempted the backup on just one running machine. I have also attempted it on a powered off machine.

I eventually got to the point where I re-formated the whole Hyper-V-1 hyper-V server and started from scratch. I then put the virtual machines back on the freshly installed server. Same results.

I have disabled any virus protection and firewalls on both the DPM server and Hyper-V-1 with no change as well.

Lastly, the DPM server has 2.7 TB of data storage, and is using less than half of that, so plenty of storage available.

I have been trying to figure this out for a couple weeks now. In the meantime I have just been manually backing up files onto a USB drive.

Thanks for any suggestions. I would be happy to hand over any log files / etc if that helps.

~ Ben

 

 

0
Comment
Question by:amritaaroma
  • 3
4 Comments
 
LVL 32

Accepted Solution

by:
Rodney Barnhardt earned 250 total points
ID: 35020212
Usually slowness or inconsistent replicas are caused by network issues. Below is a checklist of items: http://technet.microsoft.com/en-us/library/bb809059.aspx

The slowness could also be a memory leak as noted by several people having this problem: http://support.microsoft.com/kb/958387
0
 

Author Comment

by:amritaaroma
ID: 35020553
Thank you, rbarnhardt. I will review the information you have provided and let you know if anything helps out.

Thanks

~ Ben
0
 

Assisted Solution

by:amritaaroma
amritaaroma earned 0 total points
ID: 35059206
I have finally resolved this. After further research, my network card or network switch did not work with TCP Window Scaling. I disabled TCP Window Scaling for the particular Hyper-V server and replicas are created quickly and successfully.

Solution was found via the last post on:
http://social.technet.microsoft.com/Forums/en-US/itprovistanetworking/thread/c3fc9f5d-c073-4a9f-bb3d-b7bb8f893f78/

More info on TCP Window Scaling:
http://8help.osu.edu/3253.html
0
 

Author Closing Comment

by:amritaaroma
ID: 35115309
I have accepted my solution as an answer as well because it provides additional research and information that ultimately solved the issue.
0

Featured Post

3 Use Cases for Connected Systems

Our Dev teams are like yours. They’re continually cranking out code for new features/bugs fixes, testing, deploying, testing some more, responding to production monitoring events and more. It’s complex. So, we thought you’d like to see what’s working for us.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you ever consider purchasing any Daossoft Software Products, DON'T expect any meaningful support - This article should convince you why!
Facing problems with you memory card? Cannot access your memory card? All stored data, images, videos are lost? If these are your questions...than this small article might help you out in retrieving your lost or inaccessible data.
In this Micro Tutorial viewers will learn how they can get their files copied out from their unbootable system without need to use recovery services. As an example non-bootable Windows 2012R2 installation is used which has boot problems.
This tutorial will show how to configure a single USB drive with a separate folder for each day of the week. This will allow each of the backups to be kept separate preventing the previous day’s backup from being overwritten. The USB drive must be s…

803 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question