“Mail server crashed” worst nightmare for a System admin. Followed by tight Dead lines, incident reports, load of complains you have to listen to, Its a full fledged disaster.
In this scenario its a medium size business with with just one single Server running AD and Exchange 2010(not ideal i know) which was upgraded from SBS 2003
AD and DNS failed after de-commissioning the old SBS server.
Recovering from full server backup was not an option and we had the Databases on a separate drive.
Important things to keep in mind when recovering DB’s on a different AD domain
- Organization name and the Exchange Administrative Group should be the same in order for the Portability feature to work
- Database must be in a clean shutdown state
- After mounting the old DB’s always move the mail boxes to new database’s
- Exchange 2010 Slandered only supports up to 5 Databases.
there are few method’s to recover DB’s on exchange 2010, This is the method we used.
Check List before proceeding further
Once you have
- Restored the Old Databases from backup to a different location on the server
- installed the AD (with the same domain name) and the Exchange with the same Administrative Group as the earlier
Preparing the Databases
Checking the statues of the database file
in order for the Database portability feature to work. we need the DB’s in clean shutdown state. To check the Database State we are gonna be using the Exchange Server Database Utility’s file dump mode
Note : if you are restoring from a windows Backup the Database should already be in a Clean shut down state as the exchange VSS backup re-plays the log files before backing up the DB
More Detail on eseutil /MH – link
Launch command prompt and type
eseutil /MH “D:RestoreoldDB.edb” (the text in blue is the location of the restored old database file)
Check the output you get and check if the DB is in a Dirty shutdown or a clean shutdown state
If the DB file is in Dirty shutdown state
In this case we did not have any recent backups and we were not able to soft recover the DB since this is a new DC. so we had to do a hard recovery using this command.
eseutil /P “D:RestoreoldDB.edb” (the text in blue is the location of the restored old database file)
Click ok on the prompt to continue
Note : using the Hard recovery will result in loss of information depending on the amount of log files you have for that Database
After the Hard recovery to fully rebuild indexes and defragment the database
eseutil /D “D:RestoreoldDB.edb” (the text in blue is the location of the restored old database file)
Mounting the Database using the Portability feature.
Create a new Database
Create a new Database for example we will create one named – recoveryDB1
Go to properties of the new DB > Maintenance Tab > Select the option “This Database can be overwritten by a restore”
Apply the Changes and dismount the Database
Replace the new Database file with the Repaired Database
Firstly go to the folder where the new DB file(recoveryDB1.edb) is located and Rename or delete it
Delete the log files / Catalog files
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Rename the Recovered Database
Go to the Folder where the Database we repaired before is located and Rename it to “recoveryDB1”
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Replace the newly created Database
Copy the Repaired DB file and replace the new Database file recoveryDB1.edb
Remember the Log files should be deleted or moved before you mount this DB.
Mount the “recoveryDB1” Database From EMC
now the mailStore should be mounted with out an issue
Errors you might run in to
In case you do get errors when mounting the DB such as
Operation terminated with error -1216 (JET_errAttachedDatabaseMismatch, An outstanding database attachment has been detected at the start or end of recovery, but database is missing or does not match attachment info) after 11.625 seconds.
you are getting this error because The DB is in dirty shutdown state, refer to the Preparing the Database Section above to fix the issue by performing a Hard Recovery
unable to mount error ‘s
The new Database Log files are still present, Delete them or move them.
Now you can go ahead and Attach the Mailboxes to the corresponding user accounts.
Word of advice
It will be wise to not to keep this recovered Mail Store in production for long. you will run in to various issues as the Mails start to flow in and out
Create new Mail stores’s and Move the mail boxes to avoid future problems.
Some mailboxes might be corrupted. in that case
Easiest way is to use the
“New-MailboxRepairRequest” cmdlet
Refer to this tech-net article for more info – link
Or
- Export it to a PST
- Attach the user to a fresh mailbox
- Sync back the Data you need through outlook
