Extending the Real-Time Communications Functionality of Exchange Server 2007 : Installing OCS 2007 (part 1)

OCS 2007 has a surprisingly complex installation process at first glance. What Microsoft has done, however, has been to divide up the installation process into multiple sections, providing for checks along the way so that there is less room for error. Because the installation requires an Active Directory schema upgrade, it is important that the process run smoothly, so it is good that this process is designed the way it is.

Extending the Active Directory (AD) Schema

OCS 2007 integrates deep into an existing AD environment. It integrates so deeply, in fact, that an extension of the underlying AD schema is required before the product can be installed. AD schema upgrades are no small thing, of course, so it is wise to become familiar with the consequences of extending the schema and to make sure that a backup of the domain takes place first. To start the installation process, perform the following steps:

1.	Run the OCS 2007 setup program from the media. Click on the deploy.exe file.
2.	From the Deployment Wizard, click the Deploy Standard Edition Server link.
3.	Review the steps on the subsequent dialog box for the Deployment Wizard, shown in Figure 1. Click Prepare Active Directory. Figure 1. Deploying OCS 2007. Caution Installation of Office Communications Server 2007 requires an AD schema upgrade to the AD forest. It is important to fully understand the consequences of a schema upgrade in advance, as an upgrade will replicate to all domain controllers in a forest.
4.	In the subsequent dialog box, shown in Figure 2, click Run to start the schema upgrade process. Figure 2. Starting the schema upgrade process.
5.	At the Schema Preparation Wizard welcome screen, click Next to begin the process.
6.	In the Schema File Location dialog box, leave the default location selected, and click Next.
7.	At the review screen, review the settings and, keeping in mind the caution previously given about schema upgrades, click Next to continue.
8.	The schema upgrade process will begin, as shown in the dialog box in Figure 3. When it is complete, click Finish. Figure 3. Extending the schema.

After the schema update has run, be sure you wait until the new schema extensions have replicated to all domain controllers in the forest. After this has been verified, return to the Deployment Wizard to continue.

Preparing the AD Forest

After the schema extension is complete, perform the following steps:

1.	Return to the Deployment Wizard and click Run under Step 3: Prep Forest, as shown in Figure 4. Figure 4. Prepping the forest.
2.	Click Next at the welcome screen of the Forest Preparation Wizard.
3.	The subsequent dialog box, shown in Figure 5, gives you the option to choose between storing the global settings in the root domain, or in the configuration partition. In most cases, install in the root domain. Figure 5. Choosing where to store global settings.
4.	Under Domain, choose the domain where OCS will create the groups used by the server. This is typically the main resource domain where the servers are installed into. Click Next to continue.
5.	At the review screen, click Next to continue.
6.	Click Finish.

After this step is complete, ensure that replication of the newly created objects has occurred on all domain controllers in the forest and proceed to the next step.

Prepping the Domain

The following procedure must be run on each domain in the forest where OCS will be installed:

1.	Click Run under the Prep Current Domain listing in the Deployment Wizard.
2.	From the Domain Preparation Wizard, click Next to continue.
3.	From the Domain Preparation Information dialog box, review the warning illustrated in Figure 6, and click Next to continue. Figure 6. Prepping the domain.
4.	Click Next at the review dialog box.
5.	Click Finish.

Once again, make sure replication takes place before advancing to the next step in the installation process.