Slow Mailbox Migration “within” Exchange 2016 databases on same server

exchange-2016mailboxmigration

We have recently migrated from exchange 2010 to 2016. Everything went smooth until one day we had to fail Veeam replication to DR site. One of the databases crashed and had to be restored from backup. since then, this database frequently goes in dirty shutdown and has to be mounted with -AcceptDataloss switch.
In short, we decided to move mailboxes from this database to a new one. There are around 175 mailboxes with 350 GB data. We are trying to migrate in batches of 10s and 15s but its verrryyyyy slow. it takes days to migrate 4-5 users. i enabled exchange throttling for this activity as recommended on
" https://justaucguy.wordpress.com/2018/08/24/slow-mailbox-moves-in-exchange-2016/ " but still not getting 100%.

Anyone can give any idea or suggestion?

Best Answer

What about trying the operations mentioned in this similar case?

“MSExchangeMailboxReplication.exe.config” file located at “C:\Program Files\Microsoft\Exchange Server\V15\Bin”

Change ExportBufferSizeKB=”512″ to 10240 and restart 'Mailbox Replication Service'
Disable indexing temporarily and enable it back once you complete migration. Set-MailboxDatabase “DB1” -IndexEnabled:$False
Change MRSThroattling value from 1 to 0 here and restart 'Mailbox Replication Service'. As usual, re enable it back once migration is finished. HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\MSExchange ResourceHealth
Another setting is set the priority as follows

New-MoveRequest -Identity “user@domain.com” -TargetDatabase “DB1” -Priority emergency

Remember that this last settings is applicable for only one mailbox. Set it for multiple mailboxes and see how it goes

Related Solutions

Exchange mailbox move-request from 2013 to 2016 gets stuck at Initial Seeding

I found a simple solution to this problem: Downgrade your Exchange 2013 box.

As part of my migration plan, we had 2013 also in its own 2-node DAG. The 2nd node was brand new and had been patched up to the latest CU at the time:

AdminDisplayVersion : Version 15.0 (Build 1236.3) (Exchange 2013 CU14)

The old 2013 node was just patched enough for 2016 co-existence:

AdminDisplayVersion : Version 15.0 (Build 1178.4) (Exchange 2013 CU12)

I recalled that before I'd built the new 2013 box, I was successfully able to migrate a few 15 GB mailboxes over to 2016 without any issues.

During the course of my migrations, I had activated all the mailbox databases on the new node, so of course the CU version on the new node meant all future mailbox moves required a mailbox repair when > 10GB.

The difference is: for the older CU patch level, no mailbox repair is required over 10GB. Similar to Exchange 2010 in this sense. So because no repair/isinteg took place, the move succeeds. I am not sure exactly at what point Exchange 2013 began to require an IsInteg check as part of the migration. I am also not sure if this is "fixed" in later versions.

If need to downgrade to a lower CU, you might be able to build a new 2013 box, setup a DAG and then migrate all your databases over to the older versions.

You can see by comparing the move request reports, that IsInteg is run before any attempt is made to begin transferring the mailbox data, and this is why everything stalls.

Here's an excerpt of a move request that failed, due to the IsInteg check:

    18/03/2017 12:34:12 AM [EXCH16-SYD-01] Setting up ISInteg repair run upfront for this mailbox since it's a large mailbox. "Primary mailbox size = 11120110046, Archive mailbox size = 0, Large mailbox size threshold config value = 10737418240

    ...

    18/03/2017 12:52:58 AM [EXCH16-SYD-01] Connected to source mailbox '6e6a0983-02ab-4d1d-84ea-d0071e7e6536 (Primary)', database
    18/03/2017 12:52:58 AM [EXCH16-SYD-01] Started Store IsInteg task for mailbox '6e6a0983-02ab-4d1d-84ea-d0071e7e6536'. IsInteg RequestGuid = 'd783655f-7e84-4afb-b6a3-0669e750041a'.
    18/03/2017 12:53:33 AM [EXCH16-SYD-01] Store IsInteg task is pending completion for mailbox '6e6a0983-02ab-4d1d-84ea-d0071e7e6536'. IsIntegRequestGuid = 'd783655f-7e84-4afb-b6a3-0669e750041a'. Percentages complete: 0 .
    18/03/2017 12:54:03 AM [EXCH16-SYD-01] Store IsInteg task is pending completion for mailbox '6e6a0983-02ab-4d1d-84ea-d0071e7e6536'. IsIntegRequestGuid = 'd783655f-7e84-4afb-b6a3-0669e750041a'. Percentages complete: 0 .

Here's an excerpt of a move request that worked, going from 2013 to 2016:

   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Connected to source mailbox '9a45c915-a87e-4211-8539-35034be5c0eb (Primary)', database

   ...

   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Request processing started.
   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Source mailbox information:
   Regular Items: 28128, 4.865 GB (5,223,415,468 bytes)
   Regular Deleted Items: 134, 8.387 MB (8,794,863 bytes)
   FAI Items: 440, 2.627 MB (2,754,276 bytes)
   FAI Deleted Items: 0, 0 B (0 bytes)
   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Source archive mailbox information:
   Regular Items: 52386, 11.77 GB (12,639,788,901 bytes)
   Regular Deleted Items: 0, 0 B (0 bytes)
   FAI Items: 1, 2.658 KB (2,722 bytes)
   FAI Deleted Items: 0, 0 B (0 bytes)
   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Cleared sync state for request
   9a45c915-a87e-4211-8539-35034be5c0eb due to 'CleanupOrphanedMailbox'.
   2/04/2017 8:22:30 PM [EXCH16-SYD-01] Cleared sync state for request
   f33ab71d-170b-4d55-bbfb-a9bb65db2fdc due to 'CleanupOrphanedMailbox'.
   2/04/2017 8:22:31 PM [EXCH16-SYD-01] Stage: CreatingFolderHierarchy.
   Percent complete: 10.
   2/04/2017 8:22:32 PM [EXCH16-SYD-01] Initializing folder hierarchy from
   mailbox '9a45c915-a87e-4211-8539-35034be5c0eb (Primary)': 1146 folders
   total.
   2/04/2017 8:22:32 PM [EXCH16-SYD-01] Folder creation progress: 0 folders
   created in mailbox '9a45c915-a87e-4211-8539-35034be5c0eb (Primary)'.
   2/04/2017 8:23:02 PM [EXCH16-SYD-01] Folder hierarchy initialized for
   mailbox '9a45c915-a87e-4211-8539-35034be5c0eb (Primary)': 1145 folders
   created.
   2/04/2017 8:23:02 PM [EXCH16-SYD-01] Initializing folder hierarchy from
   mailbox 'f33ab71d-170b-4d55-bbfb-a9bb65db2fdc (Archive)': 846 folders total.
   2/04/2017 8:23:22 PM [EXCH16-SYD-01] Folder hierarchy initialized for
   mailbox 'f33ab71d-170b-4d55-bbfb-a9bb65db2fdc (Archive)': 845 folders
   created.
   2/04/2017 8:23:22 PM [EXCH16-SYD-01] Stage: CreatingFolderHierarchy.
   Percent complete: 10.
   2/04/2017 8:23:22 PM [EXCH16-SYD-01] Stage: CreatingInitialSyncCheckpoint.
   Percent complete: 15.
   2/04/2017 8:23:22 PM [EXCH16-SYD-01] Initial sync checkpoint progress:
   0/1146 folders processed. Currently processing mailbox
   '9a45c915-a87e-4211-8539-35034be5c0eb (Primary)'.
   2/04/2017 8:24:06 PM [EXCH16-SYD-01] Initial sync checkpoint completed:
   1970 folders processed.
   2/04/2017 8:24:06 PM [EXCH16-SYD-01] Stage: LoadingMessages. Percent
   complete: 20.
   2/04/2017 8:24:06 PM [EXCH16-SYD-01] Stage: LoadingMessages. Percent
   complete: 20.
   2/04/2017 8:29:06 PM [EXCH16-SYD-01] Stage: CopyingMessages. Percent
   complete: 27.
   2/04/2017 8:29:06 PM [EXCH16-SYD-01] Copy progress: 4546/81089 messages,
   653.3 MB (684,996,208 bytes)/16.65 GB (17,874,496,811 bytes), 11/846
   folders completed.
   2/04/2017 8:34:10 PM [EXCH16-SYD-01] Stage: CopyingMessages. Percent
   complete: 28.
   2/04/2017 8:34:10 PM [EXCH16-SYD-01] Copy progress: 5536/81089 messages,
   818.5 MB (858,269,612 bytes)/16.65 GB (17,874,496,811 bytes), 11/846

Deleting database from Exchange 2016 – error

Health mailboxes CAN be deleted and actually they should if orphaned. The link provided in BastianW answer does involve System mailboxes management and does not help in managing health mailboxes. Basically, Health mailboxes creation logic has been changed in CU6 E2013 so it's ok to remove old health mailboxes.

Health mailbox will be, anyway, recreated upon MsEchangeHM service restart.
A detailed explanation on why it may be necessary to delete monitoring mailboxes can be found here: https://blogs.technet.microsoft.com/admoore/2015/03/11/exchange-2013-health-mailboxes/

Best Answer

Related Solutions

Exchange mailbox move-request from 2013 to 2016 gets stuck at Initial Seeding

Deleting database from Exchange 2016 – error

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