Hello everyone, We are using a test environnement with DC 2003 and 2008 & Exchange 2003 and 2010 which reflects part of our production environment. We have 2 DC ( 1 2003 and 1 2008 ) for a parent domain ( testexchange.ca ) and 2 DC ( 1 2003 and 1 2008 ) for a child domain( ens1.testexchange.ca ). The forest and domain functionality are at the native 2003 level. The 2003 DC have SP2, the DC 2008 have SP1, The Exchange 2003 have SP2 and the Exchange 2010 have Sp1 with the update rollup 3 installed. All the exchange servers live in the parent domain. For testing purpose, we created a mailbox database which contains 2170 mailbox ( users are all from the child domain ) in Exchange 2003. This mailbox database had a size of about 240 MB ( 239 Mo for the .edb file and 2 Mo for the .stm file ) in Exchange 2003. None of the mailbox in that database were over 75 KB ( there were empty ). Then, using the GUI of Exchange 2010, we selected all the mailbox of that database in Exchange 2003 and did a "local move request" to a newly created mailbox database in Exchange 2010. The command "get-mailboxdatabase -identity etudiants_03 | FL" for that database in Exchange 2010 gives the following output: RunspaceId : 41f1e460-4cb5-4c2a-9812-09898a6e 6715 JournalRecipient : MailboxRetention : 00:00:00 OfflineAddressBook : OriginalDatabase : PublicFolderDatabase : Public Folder Database 177808573 9 ProhibitSendReceiveQuota : 2.3 GB (2,469,396,480 bytes) ProhibitSendQuota : 2 GB (2,147,483,648 bytes) RecoverableItemsQuota : 30 GB (32,212,254,720 bytes) RecoverableItemsWarningQuota : 20 GB (21,474,836,480 bytes) IndexEnabled : True IsExcludedFromProvisioning : False IsSuspendedFromProvisioning : False DumpsterStatistics : DumpsterServersNotAvailable : ReplicationType : None AdministrativeGroup : Exchange Administrative Group (F YDIBOHF23SPDLT) AllowFileRestore : False BackgroundDatabaseMaintenance : True ReplayBackgroundDatabaseMaintenance : BackgroundDatabaseMaintenanceSerialization : BackgroundDatabaseMaintenanceDelay : ReplayBackgroundDatabaseMaintenanceDelay : MimimumBackgroundDatabaseMaintenanceInterval : MaximumBackgroundDatabaseMaintenanceInterval : BackupInProgress : False DatabaseCreated : True Description : EdbFilePath : C:\Program Files\Microsoft\Excha nge Server\V14\Mailbox\Etudiants _03\Etudiants_03.edb ExchangeLegacyDN : /o=exchangetest/ou=Exchange Admi nistrative Group (FYDIBOHF23SPDL T)/cn=Configuration/cn=Servers/c n=LABEXCH-CAS01/cn=Microsoft Pri vate MDB DatabaseCopies : {Etudiants_03\LABEXCH-MBX2010} Servers : {LABEXCH-MBX2010} ActivationPreference : {[LABEXCH-MBX2010, 1]} ReplayLagTimes : {[LABEXCH-MBX2010, 00:00:00]} TruncationLagTimes : {[LABEXCH-MBX2010, 00:00:00]} RpcClientAccessServer : LABEXCH-CAS01.testexchange.ca MountedOnServer : LABEXCH-MBX2010.testexchange.ca DeletedItemRetention : 00:00:00 SnapshotLastFullBackup : SnapshotLastIncrementalBackup : SnapshotLastDifferentialBackup : SnapshotLastCopyBackup : LastFullBackup : LastIncrementalBackup : LastDifferentialBackup : LastCopyBackup : DatabaseSize : 6.781 GB (7,281,377,280 bytes) AvailableNewMailboxSpace : 864 KB (884,736 bytes) MaintenanceSchedule : {Sun.1:00 AM-Sun.5:00 AM, Mon.1: 00 AM-Mon.5:00 AM, Tue.1:00 AM-T ue.5:00 AM, Wed.1:00 AM-Wed.5:00 AM, Thu.1:00 AM-Thu.5:00 AM, Fr i.1:00 AM-Fri.5:00 AM, Sat.1:00 AM-Sat.5:00 AM} MountAtStartup : True Mounted : True Organization : exchangetest QuotaNotificationSchedule : {Sun.1:00 AM-Sun.1:15 AM, Mon.1: 00 AM-Mon.1:15 AM, Tue.1:00 AM-T ue.1:15 AM, Wed.1:00 AM-Wed.1:15 AM, Thu.1:00 AM-Thu.1:15 AM, Fr i.1:00 AM-Fri.1:15 AM, Sat.1:00 AM-Sat.1:15 AM} Recovery : False RetainDeletedItemsUntilBackup : False Server : LABEXCH-MBX2010 MasterServerOrAvailabilityGroup : LABEXCH-MBX2010 MasterType : Server ServerName : LABEXCH-MBX2010 IssueWarningQuota : 1.899 GB (2,039,480,320 bytes) EventHistoryRetentionPeriod : 7.00:00:00 Name : Etudiants_03 LogFolderPath : C:\Program Files\Microsoft\Excha nge Server\V14\Mailbox\Etudiants _03 TemporaryDataFolderPath : CircularLoggingEnabled : True LogFilePrefix : E05 LogFileSize : 1024 LogBuffers : MaximumOpenTables : MaximumTemporaryTables : MaximumCursors : MaximumSessions : MaximumVersionStorePages : PreferredVersionStorePages : DatabaseExtensionSize : LogCheckpointDepth : ReplayCheckpointDepth : CachedClosedTables : CachePriority : ReplayCachePriority : MaximumPreReadPages : MaximumReplayPreReadPages : DataMoveReplicationConstraint : None IsMailboxDatabase : True IsPublicFolderDatabase : False AdminDisplayName : Etudiants_03 ExchangeVersion : 0.10 (14.0.100.0) DistinguishedName : CN=Etudiants_03,CN=Databases,CN= Exchange Administrative Group (F YDIBOHF23SPDLT),CN=Administrativ e Groups,CN=exchangetest,CN=Micr osoft Exchange,CN=Services,CN=Co nfiguration,DC=testexchange,DC=c a Identity : Etudiants_03 Guid : 1eeccfc4-3f7c-4b70-9251-3f342924 bd27 ObjectCategory : testexchange.ca/Configuration/Sc hema/ms-Exch-Private-MDB ObjectClass : {top, msExchMDB, msExchPrivateMD B} WhenChanged : 6/20/2011 1:25:34 PM WhenCreated : 4/8/2011 10:23:03 AM WhenChangedUTC : 6/20/2011 5:25:34 PM WhenCreatedUTC : 4/8/2011 2:23:03 PM OrganizationId : OriginatingServer : LabExch-DC2.testexchange.ca IsValid : True ------------------------------------ When I ran the command "Get-MailboxDatabase -identity etudiants_03 -status | ft identity, availablenewmailboxspace, databasesize", I got this output: Identity AvailableNewMailboxSpace DatabaseSize -------- ------------------------ ------------ Etudiants_03 864 KB (884,736 bytes) 6.781 GB (7,281,377,28... ------------------------------------ The problem we have is that this database has now a size of about 6.7 GB ( I am talking about the size of the etudiants_03.edb file ). The command "get-mailboxstatistics -database etudiants_03 | fl displayname, totalitemsize" shows that no mailbox are over 75 KB, as expected. I tried an off-line defrag of this database ( eseutil /d ), even if the "AvailableNewMailboxSpace" shows only 864K free. The command ran successfully but no changes in the size of the etudiants_03.edb file in Exchange 2010... I know that the mailbox database are expected to be bigger ( 20% - 50% more ) in exchange 2010 versus Exchange 2003, but here the difference in size seems to be way too much ( 240 MB for 2003 VS 6.7 GB for 2010 ! ). What can I do ? How can we explain this ? I tried a backup of the database etudiants_03 in Exchange 2010 ( without much hope that it would solve my problem ) with ntbackup but that didn't change anything in the size of the etudiants_03.edb file. Anybody has an idea ? We cannot migrate the users in our production environment with results like this. Thank you ! MartinSTE

Is there data published to the Exchange 2003 DB's or are they all empty? Exchange 2010 removes the use of single instance storage so you are likely to see an increase in database and mailbox sizes. But it all depends what objects are in the the mailboxes. If each had the same attachment included you potentially could see this type increase. If all the mailboxes are empty I would recommend you publish data to these boxes then retry the test. I don't believe empty mailboxes within DB's are good test items. I think you'll see much different results if you publish some data to a greater number of mailboxes.Chris Raschke | C/D/H - www.CDH.com

Thank you Chris, I will look at the beginning of next week more closely to what the mailbox contain and if they are really empty. If so, we will make sure to put some stuff into the mailbox and do the test again. I am aware of the new database schema of Exchange 2010 and the changes made to the concept of single instance storage. For sure, they are no attachments into those mailbox. Every mailbox is of size under 75 KB. I will post back the result here. Have a nice week-end, MartinSTE

Good luck - look forward to hearing the results.Chris Raschke | C/D/H - www.CDH.com

Hello Chris, We are preparing our test environnment, this is why it is taking a while to re-do the testing....

Hi MartinSTE, As you might know, Exchange 2010 SP1 doesnt fully delete the a mailbox from the database after the mailbox has been removed, moved to a different database etc.. If you are in a Transition Senario, you might have moved mailboxes back and forth and now have a lot of SoftDeleted Mailboxes in the database. That would at least explain why the database edudiants_03 is bigger than expected. Run this to find out: Get-MailboxStatistics -Database etudiants_03 | where {$_.DisconnectReason -eq "SoftDeleted"} | ft Displayname, totalitemsize, disconnectdate For more information, have a look at these Technet Articles: Disconnected Mailboxes http://technet.microsoft.com/en-us/library/bb232039.aspx Permanently Delete a Disconnected Mailbox http://technet.microsoft.com/en-us/library/gg181092.aspx Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question.

Hello Miskovic, Thank you for your input into this discussion. Unfortunatly, we are preparing our test environment for another test and because of that, the old database etudiants_03 ( and all the others ) have been deleted. I cannot verify now but I will in another test, hopefully this week. When we did the first test, it was a one way move from every mailbox in the Exchange 2003 mailbox databases to the new Exchange 2010 mailbox database. So I am not sure if soft deleted mailbox played a role in the huge sizes of the Exchange 2010 mailbox databases. I will however pay extra attention to what you're saying. I will post here the results of the new test ( with non-empty mailbox ) soon I hope. Thank you ! MartinSTE

Hello Everyone, Sorry for the delay in this follow-up. We ran the test again. We created the mailbox database on the Exchange 2003 and sent 2 e-mails to each mailbox users in that 2003 database. Before moving the mailbox users, I looked into the 2003 mailbox database to make sure it shows that there was 2 items into the mailbox of each users ( the 2 e-mails sent to each users before ). Total number of users moved from the 2003 database to the 2010 database: 1227. Total size of the destination EDB file ( 2010 ) after the move: 4 Go. The total size of the database on the exchange 2003 was about 40 Mo before the move. I ran the following command after the move ( I changed the displaynames for privacy reasons ): ---------------- [PS] C:\Windows\system32>Get-MailboxStatistics -Database etudiants_00 | where { $_.totalitemsize -gt 100000 } | ft displayname, totalitemsize DisplayName TotalItemSize ----------- ------------- user1, user1 104.4 KB (106,910 bytes) user2, user2 105 KB (107,527 bytes) user3, user3 105.3 KB (107,831 bytes) SystemMailbox{3e0c6849-fff3-48b7-9403-11ceccbb21cd} 77.82 MB (81,596,756 bytes) ---------------- I ran the command above to find out if there was a mailbox that was taking up all the space. It appears that the biggest mailbox is the SystemMailbox that is only 77 Mo. That does not explain the fact the database ( EDB file ) on Exchange 2010 is now 4 Go. I also ran the following command ( no errors but no list shown ): ---------------- [PS] C:\Windows\system32>Get-MailboxStatistics -Database etudiants_00 | where {$_.DisconnectReason -eq "SoftDeleted"} | ft Displayname, totalitemsize, disconnectdate ---------------- The following command is supposed to give the "white" space available in the etudiants_00 mailbox database on Exchange 2010: ---------------- [PS] C:\Windows\system32>Get-MailboxDatabase -Identity etudiants_00 -Status | ft name, AvailableNewMailboxSpace Name AvailableNewMailboxSpace ---- ------------------------ etudiants_00 24.25 MB (25,427,968 bytes) ------------------ So there's 1227 users in that mailbox database on Exchange 2010, 4 of them have a mailbox higher that 100k ( with the biggest one being the systemmailbox with 78 mo ), and the EDB file on Exchange 2010 is about 4 Go...White space available in the database is about 25 mo, so this is not the issue... I do not understand. Am I missing something ? MartinSTE