The sooner you start, the sooner you can migrate

Your Exchange Server 5.5 system is running efficiently, and you're content with Windows NT 4.0's behavior. You know how to make messages flow without hindrance, and you understand the ins and outs of the OS. Enjoy your fleeting comfort, because your technical landscape is about to change with the arrival of Windows 2000 (Win2K) and Microsoft's next major functionality release of Exchange Server—Platinum. The new OS and messaging server are so different from previous versions that they'll force you to reassess how you design and plan an Exchange Server implementation before you proceed with a migration to Platinum. You need to keep in mind lessons you learned from previous successful implementations.

Platinum offers abundant functionality. If you're interested in collecting, categorizing, and using knowledge more efficiently than you do today, you'll want to move to Platinum sooner rather than later. In this article, I discuss the eight steps you need to take to prepare for Platinum. You can take some of these steps immediately, but you'll need to complete others later. The sooner you start, the sooner you can migrate.

Your complete Platinum deployment plan needs to describe in detail each of the eight steps that follow. The plan must also state when each activity will occur, who is responsible for the task, and what dependencies exist (e.g., the availability of essential Exchange Server add-ons).

1. Gather Knowledge
Software installation routines attempt to make everything appear simple and straightforward. But if you rush to install software without understanding the technology, you'll probably make a mistake. If you err while installing Win2K or Platinum, you might need to completely reinstall the software. Before you attempt deployment, take the time to learn about the new technology.

Attend training classes and seminars so that you can set the scene and understand the work you'll have to do to install Win2K and Platinum. Getting your hands dirty reinforces book learning, so when you return from training, take the time to install public betas on your test systems. Don't stop at only one server, unless your production environment includes only one server. We live in a networked and distributed world, which your test environment needs to reflect. Install at least two servers to test the network components.

2. Prepare Your Exchange Server Environment
Exchange Server 5.5 is the gateway to Platinum. You can't upgrade to Platinum from any other version of Exchange Server, so ensure that all your servers are running version 5.5 with the latest service pack (Service Pack 2—SP2—at press time). Many servers still run Exchange Server 5.0 or 4.0, simply because no one has upgraded the software (or applied all the associated NT upgrades and third-party add-ons). Why upgrade a server that's doing its job?

A Platinum installation requires upgrades to many database internals, but performing several successive internal upgrades during an installation isn't feasible. Suppose you have an Exchange Server 4.0 system with a 6GB Information Store (IS). The database will upgrade when you move to Exchange Server 5.0 and will upgrade again when you move to Exchange Server 5.5. The time that each upgrade will require depends on your computer's speed and the size of the databases. Each of these database migrations might take 3 hours or more (and you'd still have other upgrade operations to perform). If you're planning to upgrade from Exchange Server 4.0 to Platinum, you'll require an extra migration step that will make the elapsed time unacceptable. If anything goes wrong in such a complex undertaking, the recovery will be time-consuming. Thus, you need to apply upgrades over time and stabilize the system between each step.

Simplifying the upgrade process isn't the only reason why Exchange Server 5.5 is the gateway to Platinum. Exchange Server 5.5 is the first release to support a read-write version of Lightweight Directory Access Protocol (LDAP) 3.0. The Active Directory Connector uses LDAP to link—and provide bidirectional synchronization between—the Exchange Server 5.5 Directory Store and Win2K's Active Directory (AD). Platinum doesn't have a built-in directory. Instead, Platinum stores details about mailboxes, distribution lists (DLs), and recipients (contacts in Win2K) in AD and extends the AD schema to store additional attributes that Exchange Server requires, including details about email servers. You can't complete a Platinum migration overnight, so synchronizing the two directories is important. If you don't synchronize them, Exchange Server 5.5 users won't be able to see Platinum users in their Global Address List (GAL), and vice versa.

Finally, understand that you must have Exchange Server 5.5 SP2 before your server meets Microsoft's Year 2000 (Y2K) readiness criteria. Depending on your components, Exchange Server 5.0 and 4.0 systems might run successfully in 2000, but Microsoft won't support them.

3. Prepare Your IP Infrastructure
Win2K depends on a solid TCP/IP infrastructure. Although Win2K supports NetBIOS, IP is the OS's default network protocol. You need to review your network to make sure that all IP addresses and subnets are valid. You also need to understand DNS. Win2K still supports WINS, but only for backward compatibility with NT 4.0. Win2K and Platinum use DNS for routing information, so you need to plan to introduce DNS if it's not already in use. If DNS is in place, you must decide whether you need to modify the existing DNS server to accommodate your move to Platinum. For example, you might decide to group all Platinum servers in one DNS zone.

You also need to decide what type of DNS server to use. Win2K uses service records (SRV records) to register services such as domain controllers, Global Catalogs, and LDAP for the AD. SRV records map services to hosts and let clients find services they need. Typically, Dynamic DNS automatically adds the SRV records each time a domain controller boots. (Newer DNS servers support Dynamic DNS.) The DNS server that Win2K includes (and UNIX DNS servers that support Berkeley Internet Name Domain—BIND—8.0) supports both SRV records and dynamic updates. If your network currently uses an earlier version of DNS (such as BIND 4.0), you don't have support for Dynamic DNS and SRV records, so you need to upgrade.

4. Plan Your Win2K Rollout
Now you can proceed to draw up your Win2K design. You need to decide what domains you want to use and how to arrange those domains in AD's forest and tree structure. You also need to decide which computers will serve as domain controllers and which computers will act as Global Catalogs. The Global Catalog is Platinum's incarnation of the Directory Store. Like the Directory Store, which contains replicated information about mailboxes, distribution lists, and other email addresses (e.g., external users addressed through SMTP) from sites throughout an Exchange Server organization, the Global Catalog contains a replicated read-only subset of information about users and contacts from a forest of domains. Fortunately, the subset that the Global Catalog maintains is enough to provide a GAL to MAPI clients such as Microsoft Outlook 2000. Instead of connecting to the Directory Store to resolve email addresses and otherwise access the GAL, a Platinum server redirects connecting MAPI clients to a Global Catalog. POP3 and IMAP4 clients will simply switch to the nearest Global Catalog to access the Directory Store and will continue to use LDAP to retrieve information.

The correct order for implementing the underlying infrastructure for Platinum is Win2K, DNS, then AD. All these components must be in place before you install your first Platinum server. Exchange Server 5.5 SP2 runs on Win2K, so you can initially implement Win2K for authentication purposes, then swap out NT 4.0 domain controllers before proceeding with the migration.

After you have some domain controllers in place and a basic AD store up and running, you can use the ADS to connect AD to the Exchange Server 5.5 Directory Store. You'll need one connection agreement between each Exchange Server site and the AD. One Active Directory Connector can handle multiple connection agreements, but in a distributed organization you'll probably run several connectors to split the load and management tasks. The synchronization will populate AD and let you acquaint yourself with the management tasks that you need to perform to keep AD healthy.

5. Get Ready for AD
The AD and the Exchange Server 5.5 Directory Store share many attributes. The two directories' similarities in concepts, terminology, and implementation will help Exchange Server systems administrators approach AD. However, although the directories share core characteristics, you must understand some key differences.

First, you can take the Exchange Server 5.5 Directory Store offline to perform maintenance, such as database compaction, without affecting other NT applications. The only applications that the Directory Store's nonavailability affects are Exchange Server and any third-party extensions. Although you can use a utility (i.e., Platinum's Esentutl—the new incarnation of Exchange Server 5.5's Eseutil) to rebuild the AD database, taking a domain controller offline for this purpose might affect client authentication and block access to all applications.

A second difference between AD and the Directory Store involves replication. Administrators often compare Exchange Server's directory-replication mechanism to a black hole, because the internal workings of replication (e.g., how you control the replication load) are sometimes a mystery. However, since 1996, Exchange Server administrators in many different production environments have built a body of knowledge. Today, most Exchange Server administrators are configuring and controlling object replication across their enterprise. AD's replication mechanism is similar but more sophisticated—replication occurs at an attribute level rather than an object level, and safeguards control replication activity within the network. If AD didn't offer safeguards (e.g., propagation dampening, which stops unnecessary replication between domain controllers), an excessive amount of replication might build up. Large queues of replication messages between sites can accumulate quickly. Also, AD uses a multithreaded agent instead of Exchange Server's single-threaded equivalent, so replication between domain controllers will occur faster. Table 1 compares key characteristics of Exchange Server 5.5's Directory Store and Win2K's AD. (Table 1 uses the term site to describe a collection of servers that a LAN-quality network connects. Differences between an Exchange Server 5.5 site and a Win2K site exist, especially in the function each site serves, but the sites require the same connectivity.)

6. Review Your Exchange Server Infrastructure
Before you proceed with your Platinum deployment, you need to conduct a thorough review of your existing Exchange Server infrastructure. As with any system migration, the task's level of difficulty relates directly to the number of computers involved. Migrating to Win2K and Platinum will be easier if you can reduce the number of account domains, computers, and sites. A review of your Exchange servers and sites might reveal places where you can consolidate older servers into larger systems or combine sites to form a more compact organization. Advances in hardware—especially in fast, reliable disks and controllers—mean that you can now support several thousand mailboxes on one server. Network upgrades might let you combine sites simultaneously, which would further reduce the migration's complexity. To advance scalability, Platinum will support virtual servers composed of a set of front-end (i.e., protocol access) and back-end (i.e., storage) computers. Single servers supporting user communities with tens of thousands of users should appear soon.

Third-party tools can aid your consolidation and migration. FastLane Technologies' DMSuite provides tools to consolidate NT domains, and Entevo's DirectManage provides a single management interface to Exchange Server, NT, and AD. Microsoft recently announced that it will license software from Mission Critical Software to help deploy Win2K in customer projects that Microsoft's Consulting Services division oversees.

Although Exchange Server 5.5 SP2 provides the Move Server Wizard (MSW), consolidating Exchange servers and sites remains difficult, because the MSW fails to eliminate a lot of necessary work before and after you move a server. Servers with large databases (e.g., larger than 4GB) move slowly. Every server you move generates much replication activity, so you can't move many servers concurrently. You need to move one server at a time and let the organization stabilize before you proceed to the next server.

7. Investigate Your Add-Ons
Today, few Exchange servers run only Exchange Server. Most implementations run a collection of third-party programs that contribute to the service Exchange Server delivers to users. After the Melissa virus scare, most Exchange administrators are convinced that their servers need the protection of an antivirus product. Backup products such as VERITAS' Backup Exec, Computer Associates' ARCServeIT, or Legato Systems' NetWorker are common add-ons for Exchange Server, as are document-management and workflow products. The list of third-party Exchange Server add-ons is long.

Platinum adds features that might eliminate the need for some third-party products. But it doesn't offer virus protection, extended backup functionality, sophisticated document management, or complex workflow. You'll still need to install extensions to get those features. List the third-party products you use, and verify that your current versions support Win2K and Platinum or that the vendor has planned an upgrade that will take advantage of Platinum's new features (e.g., serverside events).

If you choose to upgrade to Win2K first and move to Platinum later (which I recommend), you'll run Exchange Server 5.5 on Win2K for a time. Therefore, your third-party products need to work in that environment. You need to test each product before you put it into production, so make sure that your deployment plan includes a testing schedule.

Existing clients should be able to easily connect to Platinum. Many users will still run the original Exchange 4.0 client or an early version of Outlook. Some will use Outlook Web Access (OWA) and Microsoft Internet Information Server (IIS), which connects browsers to Exchange Server mailboxes and public folders. Other users will be content with IMAP4 or POP3 clients. Platinum considerably upgrades the support that Exchange Server provides to browsers; however, only newer browsers such as Internet Explorer (IE) 5.0 will experience the increased performance and stability that the implementation of a URL-addressable namespace for all Exchange objects promises.

If your company is considering implementing Win2K Professional (Win2K Pro) on the desktop as part of its overall Win2K deployment strategy, you probably also want to consider a client upgrade as part of the same operation. But if you want to use Platinum on your existing desktops, you need to include desktop testing in your deployment plan to make sure users can continue to access Exchange Server. At the same time, remember to check any clientside customizations, such as Outlook add-ons or electronic forms.

Before you perform any upgrades, you need to know how to protect data and recover from a disaster. For example, though you know how to restore an offline IS backup and get an Exchange Server 5.5 system up and running on new hardware, will the same procedure work on Platinum? What steps will you need to take to roll back a server upgrade that runs into problems? You also need to ensure that your company updates its operational procedures to accommodate AD and Platinum backups.

8. Deploy Platinum
After you've met all the prerequisites, the upgrade from Exchange Server 5.5 to Platinum is fairly straightforward. You'll learn new terms and discover new features, such as Information Storage Groups, but you'll probably recognize these terms from test installations. Platinum completely revises the message routing and transport core, and the old Message Transfer Agent's (MTA's) role in communications is now subsidiary to older Exchange Server 5.5 sites and non-SMTP connectors (e.g., Lotus Notes, cc:Mail, Microsoft Mail). SMTP becomes the predominant routing technology, and administrators will need a little time to get used to the way Platinum routes messages between servers. Platinum's use of Internet protocols (whenever possible) is a welcome development, because Internet protocols simplify the connection of different email systems with Exchange Server.

Teething problems always accompany a new product's introduction, and I anticipate more problems in the routing and transport core than anywhere else. However, I have no concerns about the product's stability. Exchange servers cope with wildly different connections to all manner of email systems, and I don't expect Platinum's developers to trap every glitch before the product's initial release. After all, that's what service packs are for!

For More Information
Information about Platinum will become more available as the ship date approaches. The Microsoft Exchange Conference 99 (MEC '99—Atlanta, Georgia, October 4-7; Hamburg, Germany, October 11-15) will feature many Platinum sessions. Details about MEC '99 are available at http://www.microsoft.com/ corpevents/mec99. If you can't attend MEC '99, Microsoft typically posts the sessions' PowerPoint presentations on its Exchange Server Web site. Last year's sessions are available at http://www .microsoft.com/ exchange/55/gen/mec98.htm. To maximize each session's presentation, you can listen to a recording of the session while viewing the slides. Tapes of MEC sessions are available from Mobiltape (http://www.mobiltape.com). Mobiltape also offers tapes of TechEd 99 Platinum sessions.

Computer book publishers will inevitably base early Platinum books on beta code. Important details might change between these books' code and the code that you run.

Swynk.com (http://ls.swynk.com) and Slipstick Systems (http://www.slipstick.com/index.htm) are other good Platinum resources. Don't expect many concrete how-to discussions in the mailing lists until other administrators have had time to play with Platinum. Nevertheless, these are invaluable resources for every systems administrator. You might think your mistakes and lack of knowledge are particular to you, but someone else out there probably shares your experience and might have a solution.

Platinum isn't a product you can install without forethought. Careful planning and testing are the keys to successful deployments. Taking Exchange Server into the Platinum age requires much preparation, but when you're ready, the effort will make your migration project all the more worthwhile.