MS Exchange Server Failover

Note: If you are performing an On-Demand Target Failover, then you will need to first install MS Exchange Server on the target server, and create and configure the necessary storage groups and empty databases, and any other necessary MS Exchange Server Prerequisites. To make this task easier and quicker, you may want to run Exchange Setup in Disaster Recovery mode (/DisasterRecovery switch). This option is only available for MS Exchange Server 2003 and higher.

In Disaster Recovery mode, Setup uses the information stored in Active Directory to recover configuration data that was lost. You can also use this method to rebuild a failed primary server. To run MS Exchange Server setup in this mode, issue the following command in the drive where the MS Exchange Server setup disk is located:

Setup copies the information from the Active Directory directory service-stored information, and then registers the same components that existed on this server before the problem that caused loss of data on the server. After Setup with the /disasterrecovery switch finishes installing the Exchange Server binary files, you can then perform an On-Demand Target Failover to the target.

In general, two things need to happen to failover to an Exchange standby server:

If failing over to different standby server than the primary (e.g. different NetBios name) and you are not using Exchange Virtual Servers with clustering, then you will need to tell Activie Directory that all the user's mailboxes have moved to a new Exchange server by reconnecting the accounts to the new mailboxes. This is not necessary if the standby server will be replacing the primary server and will have the same IP Address and Hostname as the primary, or if you play some tricks with your DNS so that the standby server takes over the name and IP address of the failed primary server.

If you are using MS Exchange Server 2007 you can use either the Move Mailbox wizard or the Move-Mailbox cmdlet. To use the Move Mailbox wizard, you must go to the action pane in the Exchange Management Console. To use the Move-Mailbox cmdlet, you must use the Exchange Management Shell. See the following Microsoft TechNet article for more detailed information: http://technet.microsoft.com/en-us/library/bb124797(EXCHG.80).aspx

2)	If you are recovering a small number of mailboxes, you can link the mailboxes to Active Directory accounts as follows (works with MS Exchange Server 2000 or 2003):

a)	In Exchange System Manager, locate the Mailboxes object and then right click to run the Mailbox Cleanup Agent. In the Mailboxes list, make sure there is a red X displayed next to the mailbox that you want to recover. This indicates the mailbox is not connected to an Active Directory user.

b)	Right click the mailbox that you want to recover, and then click Reconnect. A list of Active Directory accounts is displayed, and you can connect the mailbox any of the user accounts.

If you are recovering a large number of mailboxes and using MS Exchange Server 2003, you can use the Mailbox Recovery Center in Exchange System Manager. With Mailbox Recovery Center, you can perform reconnect or export operations on multiple disconnected mailboxes at one time. See the following Microsoft article for more information on using this tool: http://technet.microsoft.com/en-us/library/aa996202.aspx.

4)	Use the Mbconn utility (Mbconn.exe) to connect the mailboxes to the accounts. (Exchange 2000) See the following Microsoft article for more information on using this tool: http://support.microsoft.com/kb/271886

Next, go to Step 5 in the Standby Server Failover section to point your users/application to the new primary server.