Restore Exchange 2013 DAG

Suppose you have a two server setup Exchange 2013 DAG. (And an arbitrary witness machine). You would like to physically relocate the servers. Therefore, you shutdown Machine_A then Machine_B then the witness. After you have relocated the server, you think that you can leave soon. But suddenly, Machine_B has serious main broad problem and cannot start again……   Then…  Because Machine_A was shut down earlier…  The failover cluster refuses to start…  And the whole Exchange system is down….

Use the command in the link below to force cluster to start… using the  forcequorum option.

net start clussvc /forcequorum

Now, the failover cluster is up.. But Exchange is still refuse to start because the mailbox database copy in Machine_A is not the latest version…

So you need to force the copy in Machine_A to active by using the method in this link.

You may also discover that the copy queue length is 9,223,372,036,854,775,766 long…

Move-ActiveMailboxDatabase DB01 –ActivateOnServer YOUR_SERVER_NAME -SkipLagChecks -SkipActiveCopyChecks –
MountDialOverride:BESTEFFORT -SkipClientExperienceChecks

But be careful !!!, you may lose some email with this command. !!!!  Use at your own risk!!!

Do this on all Mailbox database. After you have brought the database containing your administrator login, you can login to ECP.

Then we can setup a new machine to replace the old one. Install windows, update it, use the IP of the old machine, use the same computer name. Install Exchange server prerequisites.  Consult the documents when you install the Exchange server before.

The procedure is in this link:

But in step 5, you may need to use
setup /m:RecoverServer /IAcceptExchangeServerLicenseTerms
Instead of
setup /m:RecoverServer

After adding back the DAG members, you need to force it to reseed…

This link will help:

But the
Update-MailboxDatabaseCopy -Identity <DBNamedestinationservername> -SourceServer <sourcemailbox server> -DeleteExistingFiles
command will fail with error…  You may need to wait for about 10 minutes after running Suspend-MailboxDatabasecopy command in order to successfully run it.

And that, the Update-MailboxDatabaseCopy will block your console. If you have multiple huge mailbox databases, you need to do the first one, eat something, then copy back to do the second one.

Good luck. again, use the steps above at your own risk. To reduce risk, consider to use some paid services.

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