Installing a Local Continuous Replication (LCR) server can be pretty straight forward, however not everyone has the circumstances to have installed an Exchange 2007 server and fewer a mailbox server with LCR. What is LCR?  It is a single server mailbox data redundancy solution and is an excellent choice for smaller offices that either don't need or cannot afford a complex cluster.

When obtaining hardware for a LCR server it is important to have a minimum of five volumes:

• C: Windows/Exchange Install
• L: Logs active copy
• S: Database active copy
• M: Logs passive copy
• T: Database passive copy

If you have I/O contention you can also create more volumes for additional storage groups and and a volume for the Exchange install. To make failover and failback easier each storage group should be its own volume. Also, the active and passive files should be on separate disk systems attached to different storage controllers. Doing this helps to isolate any hardware problems to either the active or passive copies allowing the server to stay functioning.

Lastly it is important to note that LCR adds a bit of memory overhead to the server. When sizing a LCR server its best to add an additional 1GB of RAM to the server to handle the LCR overhead.

In this example we are going to install a mailbox server that we will configure as a LCR server. We will assume that at least one other server will be installed after this that will run the Client Access and Hub Transport roles.  (Click on the screenshots to zoon in.)

• Start with a Windows 2003 Server x64 R2 server with SP2 (this makes install easier)
• Ensure that all IP subnets and sites are defined in Active Directory
• Run setup.com

• Install the remaining prerequisites
  • Windows PowerShell
  • IIS 6.0 (Web services, do NOT install SMTP or NNTP)
  • .NET Framework Update (KB926776)
• Start the install by clicking on Step 4 of the welcome screen.

• On the introduction screen click Next.

• Accept the EULA and click Next.

• If you aren’t paranoid choose Yes (Recommended) on the Error Reporting screen and click Next.

• On the Installation Type screen choose Custom Exchange Server Installation and select the installation path and click Next.

Note: If at all possible install Exchange on a drive other than the system drive. This will help with performance.

• On the Server Role Selection screen select Mailbox Role and click Next.

• If this is your first Exchange server in the forest you will be prompted for an Exchange organization name. Here it is typical to type in your company name or something a little more generic like “Corporate” or “Messaging” so as to not have to rename the organization in case of a company name change or in case of a merger.

• Again, if this is the first server in the forest you will be asked if you need to provide access to calendar with Office Outlook 2003 and earlier clients. If you do be sure to choose Yes so that the public folder database can be created. After choosing the proper selection click Next.

• If this is the first server in the forest you will not have any Hub Transport servers so the warning that the Readiness Checks return is expected. If you are missing any other requirements you will need to exit setup and fix the listed problems. Otherwise, click on the Install button to continue. The installation process will now begin.

The installation steps will complete. If this is a new installation this includes the AD Schema update. We now have an installed and functional Mailbox role. In a production scenario you would want to also apply the latest rollup or service pack for Exchange. In order to configure LCR we need to open up the Exchange Management Console.

The first step is to move the logs and databases to the correct directories. Be default the installer places the databases in same folders as you chose for you install. I’m not sure why they can’t just prompt you for the default database directory, hasn’t SQL done that since version 6.5? To move the log files Open Exchange Management Console then expand Server Configuration in the left hand tree view and then select the Mailbox node underneath it. In the top middle pain you will see a list of all of the Mailbox roles in your organization. Select the one you want to configure and then select First Storage Group and in the action pane on the right choose Move Storage Group Path…

• The Move Storage Group Path Wizard will appear. Select both the System and Log files locations. In a typical environment these will both be the same folder. Click Move.

• The wizard will complete moving the files and updating the configuration. Click Finish.

• Now we have to move the database to the correct drive. Choose the mailbox database in the First Storage Group and select Move Database Path... in the action pane.

• The Move Database Path wizard will start. Choose the directory that you want to move the database to. This should be a separate drive than is being used for your system and your log file drive. Click Move.

• You will be prompted that the database will be dismounted for this operation. Click Yes to continue. The operation will then complete.

• Click Finish
• Now select First Storage Group and in the action pane choose Enable local continuous replication…
• The LCR wizard will start. Review the introduction text and then click Next.

• Choose the file locations for the passive copy of the log and system files for the storage group that you are enabling for continuous replication.  Click Next.

• Choose the location for the passive copy of the database. Click Next.

Review the configuration options for continuous replication and click Enable.

The replication settings will be completed and the the database will be seeded. Click Finish.

Checking in Exchange Management Console we see that the LCR replication status is Healthy.

Now that you have a LCR enabled mailbox server what do you do to manage this thing? Well, look for another post about managing failover and failback of a LCR server.