Proposed How to estimate the time taken for mailbox move time over WAN

  • Monday, May 07, 2012 9:11 AM
     
     
     We are about to relocate the Data Center overseas

    as a test, we moved a user mailbox of 450MB in size and about 30000 items in it over a dedicated WAN link 40 Mbs , 20 ms network latency. it's finished within 50 minutes. both location has CCR exchange 2007 

    the second test was moving 10 similar users ( total 4.5 GB data and 300K items ) over the same WAN link, it's finished within 2 hr 20 minutes, noticed that exchange used 4 concurent connection during the mailbox move

    the question here:

    How to calculate / estimate if i have to transfer 1000 users mailbox of average 800 MB in size and average 30000 items in it over the same WAN link ? from the second test, 4.5 GB transfferred within 2 hours 20 minutes , seems there are some "optimization" process somewhere.

    and with average EDB size about 50GB, Mailbox portability seems a bad  option

    thank you for the advice

All Replies

  • Tuesday, May 08, 2012 5:48 AM
    Moderator
     
     Proposed

    Hi Rommel NC,

    Based on my experience and user feedbacks, it is common scenario that the migration will take hours to move a mailbox which is more than 1 GB. Besides, during the move process, the mailbox is offline and user cannot access the mailbox. See http://technet.microsoft.com/en-us/library/dd298174.aspx.  

    I’d suggest you upgrade to Exchange 2010 so that we can use the new feature of online mailbox moves.  Or, you may export the mailbox to PST files in a removable disk and then packet the removable disk to the destination server. See http://technet.microsoft.com/en-us/library/ee633455.aspx.

    Hope it is helpful.

    To estimate the time taken for mailbox move time over WAN, it might need more analysis of network connection status. However, we do not have much Network related information and experience to provide a professional suggestion on this question. So I would still suggest you post the question in Network related forum to search for more professional technical support. Your understanding would be appreciated. 


    Fiona Liao

    TechNet Community Support

  • Tuesday, May 08, 2012 4:00 PM
     
     

    Hi Fiona,

    Thank you. regarding network ,  it's a dedicated network (MPLS) with 20 ms latency and no other traffic in that WAN link, we plan to increase the B/W into 100 Mbps during the migration. Removeable media is not the option either as it create lots of job exporting and importing the pst files

    OK, imagine following scenario:

    IF those 2 CCR Exchange 2007 servers are  connected via LAN 10Mbps Ethernet full duplex network. on paper,  how long does it take to transfer 1000 users mailbox of 800MB  with 30000 items  for each user?

    assuming test transfer 1 user of 800MB 30000 items about 2 hours, and exchange 2007 uses 4 concurrent connection for the mailbox move, moving 1000 users will be as simple as :

    (1000/4)*2 hours = about  500 hours?  and each user won;t be able to access their e-mail for about 2 hours

    is there any other factors need to be put into account?

    thank you Fiona

  • Tuesday, May 08, 2012 4:12 PM
     
     

    Hi

    Something else to add to your calculations is the possibility to increase the number of threads for mailbox moves.  This is done using the MaxThreads parameter of the Move-Mailbox commandlet.  When I did a large 2007 -> 2007 migration a few years ago I found that 10 threads gave a good balance between bandwidth utilisation and database performance but it may be different in your environment.  The Exchange Console is limited to 4 threads.

    Steve

  • Wednesday, May 16, 2012 3:37 PM
     
     
    thank you Steve, will give a try
  • Thursday, May 17, 2012 2:28 AM
    Moderator
     
     

    Hi Rommel,

    I have alaready involve a next level support engineer in this thread, will post here if there is any update.


    Fiona Liao

    TechNet Community Support

  • Friday, August 17, 2012 6:10 AM
     
     Proposed
    The Maxthreads is the only way to speed up the migration, start with a value of 10 and increase based on the outcome.