This document describes steps necessary to configure Double-Take to provide high availability for Windows servers running Microsoft Exchange Server version 2000 or 2003. These procedures allow a secondary server to assume the identity and role of a failed Exchange server while maintaining the availability of Exchange services with minimal disruption or data loss.

That means that users will have access to the same mailboxes and public folders on a uniquely named target server that existed on the source server prior to a failure.

In addition to the Exchange Information Stores (mailboxes and public folders), there are many important aspects of an Exchange server configuration that are required for Exchange functionality following the loss of a production Exchange Server.

It is important to be aware of the overall production Exchange server configuration, and to configure the target server identically.

Requirements

1. Microsoft Windows 2003
2. Exchange Server 2003
3. Both the Source and target Servers must be in same AD Domain
4. Double take Software
5. Exchfailover utility version 1.24 from NSI Software

Preparing the Source Server

1. Install Windows 2003 Server OS and apply Service packs and patches as required
2. Join this Server to the Domain (Server should be a member Server)
3. Install Exchange 2003 Server on the Source with Service pack 2

NOTE:
Keep track of your installation selections and storage locations so that Exchange can be installed identically on the target server. You will need to know the exact names and locations for the following items:
a) Storage group names
b) Public and Private Store name
c) Log files and system paths
d) Log file prefix
e) Database names and paths
4. Install Double take Software and copy the ExchFailover.exe into the directory where double take is installed

Preparing the Target Server

1. Install Windows 2003 Server OS and apply Service packs and patches as required
2. Join this Server to the Domain (Server should be a member Server and join to the same domain as source)
3. Install Exchange 2003 Server on the Source with Service pack 2 and verify that the installation paths and storage group paths are same as source server
4. On the target server, use Exchange System Manager to configure the database so that it can be overwritten during a restoration.

a) In System Manager, right-click the server store name and select Properties.
b) On the Database tab, enable This Database can be overwritten by restore.
c) Repeat steps a and b for each information store that will be replicated from the source.

5. On the target, change the Exchange services that are automatic startup to manual startup. If an Exchange service is disabled because it is not necessary for your environment, leave the service disabled.
Microsoft Exchange System Attendant (MSExchangeSA)
Microsoft Exchange Information Store (MSExchangeIS)
Microsoft Exchange Event Service (MSExchangeES)
Microsoft Exchange MTA Stacks (MSExchangeMTA)
Microsoft Exchange Post Office Protocol (POP3Svc)
Microsoft Exchange Internet Message Access Protocol (IMAP4Svc)
Microsoft Exchange Management (MSExchangeMGMT)
Microsoft Exchange Routing Engine (RESvc)
Any other Exchange related services: Fax, Blackberry, Management software, and so on.

6. Install Double-Take on the target and reboot when the installation is complete. This will initialize Double-Take and stop the Exchange services because the services were set to manual.

7. Copy the ExchFailover.exe into the directory where double take is installed

Configuring Double-Take mirroring and replication

In this section, you will be creating your Double-Take replication set and establishing the Double-Take connection between your source and target servers.

1. On the source, open the Double-Take Management Console (Start, Programs, Double-Take, Management Console).
2. In the left pane of the Management Console, double-click on the target to login.
3. Again in the left pane, double-click on the source to login. Right-click on the source and select Properties. On the Source tab, enable Block Checksum All Files on a Difference Mirror and click OK.
4. Right-click the source and select New, Replication Set and enter the desired name for the replication set. Select your Exchange data to replicate to the target. You can use the GUI selection process or the Replication Set Properties dialog. Right-click the replication set name and select Save to save the replication set.
5. Drag and drop the replication set onto the target and the Connection Manager will open.
The Source Server, Target Server, Replication Set, and Route fields will automatically be populated. If you have multiple IP addresses on your target, verify the Route field is set to the correct network path. Select the One To One mapping so that the replication set data is transmitted to the same directory structure on the target.
6. Click Connect to start the mirror and replication processes.
7. Exchange continuously writes data to the disk causing the replication statistics in the Double-Take Management Console to constantly change, even when users are not logged in. Your data is protected after the mirror is complete and the Mirror Status has changed to Idle.

NOTE:
Be sure of the following caveats:
Select all of the Exchange directories, including the directories with the database and log files.
Exclude the \bin directory.
Exclude any application files (.dll and .exe) since Exchange is already installed on the target.
When creating a rule that excludes files based on a wildcard, you must include the full path to the wildcard. For example, to exclude all .dll files in the exchsrvr directory, the replication set rule should be c:\program files\exchsrvr\*.dll.
This completes about configuration