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Stanleyj's avatar
Stanleyj
Level 6
13 years ago

duplications from wrong media server

I have two 5200 appliances (2.0.1) one is in our primary data center and one is at our DR site connected by a 43mb pipe.  My primary appliance has two LTO tape libraries directly attached via fiber that are used for doing monthly backups.  I am using SLP's for the back up and duplications.

Every weekend we do a full backup (1.3tb) that is backed up to my primary appliance and then duplicated to my DR appliance. During this backup i notice that my media server that is being used is primary > primary (for backup) and DR > DR (for duplications).  This is perfectly fine.

Now heres the trouble.  When i mix a duplication to tape in this process the system trys to load balance the duplication between my media servers.

Meaning:

One duplication job will show the primary as the media server for the tape backup and one job will show the DR appliance.  This would all be ok if the DR appliance was on my local LAN but it is not and therefore any duplication using it as the media server to tape can take over 24 hours to complete.  In the SLP for my monthlys I have removed the DR appliance as a duplication so i dont know why it keeps responding.

Example:

i had a 245gb exchange DB duplication that was using my DR appliance as the media server and it had been running for 48hours and was only 60% complete.  I noticed the job and cancled it.  When it retried it picked up my primary appliance as the media server and in 25min it was complete (over fiber channel).

I opened a ticket with support 2 months ago but we have yet to figure out the deal.  This hasnt been that big of an issue until another group wanted to replicate some VTL's to the DR and realized that the bandwith is 100% consumed all the time by netbackup.

i have been tinkering with this for months and cannot figure out what i have configured wrong so i want to consult the almight Community for answers.  LOL!

To me it sounds like the media servers are setup so that they can load balance but i cant find were to disable that.

 

 

  • Not sure exactly what effect that would have

    However, you could run:

    nbemmcmd -changesetting -machinename mastername -COMMON_SERVER_FOR_DUP required

    That should force the original media server to run it SLP duplication, details of the setting below:

    Required. NetBackup makes an exhaustive search to find a common
    server. If the common media servers are busy, NetBackup queues the
    resource request and waits for the resources to become available. If
    no common servers are in the NetBackup domain, or if a common
    server exists but is down, NetBackup runs the job with two separate
    media servers, sending the images over the network.

    Hope this helps

  • Does anyone know if its possible to remove my second appliance as a valid media server but still have duplications run to it. 

  • You cannot  do that unless you use AIR (which I dont think is available yet in the appliances)

    However, there are some tweaks you can do to get your duplication working correctly

    See the De-Dupe Guide : http://www.symantec.com/docs/DOC3657

    Page 73 onwards covers some of the behavoir and how you can tweak it and the end of page 78 starts the discussion of load balancing

    Hope this helps

  • First thankyou for the link.  Some very good information in there.  But my issue is only when i try to do a backup to tape.

    This shouldnt involve any kind of deduplication would it?  My SLP only has a backup listed to go directly to my tape drives.  When the backups kick off my offsite appliance trys to help out with being a media server for the tape backup.

    Would unchecking the second appliance as a media server under credentails/storage servers be my possible solution for this?  The way i understand it is that setting is only load balancing the deduplication portion of the backup to disk.

  • Not sure exactly what effect that would have

    However, you could run:

    nbemmcmd -changesetting -machinename mastername -COMMON_SERVER_FOR_DUP required

    That should force the original media server to run it SLP duplication, details of the setting below:

    Required. NetBackup makes an exhaustive search to find a common
    server. If the common media servers are busy, NetBackup queues the
    resource request and waits for the resources to become available. If
    no common servers are in the NetBackup domain, or if a common
    server exists but is down, NetBackup runs the job with two separate
    media servers, sending the images over the network.

    Hope this helps

  • I just ran the command you supplied.  I read the following article and you are right.  That sound exactly like what i need.  Because both of my media servers can access the tape drive it is load balancing between the two when my primary is busy.

    According to the KB by setting the required option the job will stay queued until the media server of my choosing is available.

    http://www.symantec.com/business/support/index?page=content&id=HOWTO43719

     

    I will run a few tape jobs and see what happens. 

    If this does correct my issue it would have been nice for symantec to have included a setting like this under the media server options.

    You think when i upgrade to 7.5 in a few months i will be fighting this battle all over again?   

  • Glad this has helped - not sure of all of the 7.5 changes yet - but the command still seems to exist so hopefully you should be OK