Prepare your network
The release of Microsoft Cluster Server (MSCS--formerly code-named Wolfpack) as part of Windows NT Server, Enterprise Edition (NTS/E) 4.0 is a welcome addition to Microsoft's base NT Server offering. I work with several clients who have been waiting impatiently for Microsoft to provide a solution that supports the high availability, scalability, and ease of management that clustering has brought them on their OpenVMS and Tandem systems for more than 10 years. For better or for worse, more than a year of speculation and waiting is over.
The lack of shrink-wrapped, high availability support from Microsoft has sent many users looking for third-party data replication and mirroring products such as Qualix Group's OctopusHA+ and Vinca's StandbyServer. Other users wanting a shared storage solution similar to MSCS have turned to Digital Equipment's Digital Clusters for Windows NT and NCR's LifeKeeper for Windows NT. Still other users with fault tolerance requirements have used Marathon Technologies' Endurance 4000, and those with pressing out-of-box scalability needs have looked at Convoy by Valence Research.
Articles that describe clustering, explain why you might want it, and outline ways you might use it in your environment have already set the stage for this article (for a list of related articles and clustering product reviews, see "Related Articles in Windows NT Magazine," page 165). In this article, I'll describe how to plan for getting MSCS up and running in your environment. To begin, you need to know how to prepare your network environment for MSCS.
Getting Ready Is the Hard Part
Installing the MSCS software is straightforward and simple. However, setting up the cluster is a different matter. A cluster is much more than software: It's a carefully planned, assembled, and tested collection of software and hardware that's only part of a high availability computing environment. Many new MSCS users will initially purchase their production clusters as new, preconfigured systems. That approach is good because the time these users save on hardware configuration, validation, and support by purchasing a turnkey MSCS solution is better spent making the user's environment cluster ready.
Configuring your environment for MSCS takes a fair amount of network-related planning beyond hardware configuration and software installation issues. You have to address these issues before you have several thousand dollars of cluster parts sitting in a corner of your office and a CFO breathing down your neck.
TCP/IP Connectivity
All workstation clients accessing data on the cluster do so via TCP/IP. As a result, TCP/IP connectivity is important to the planning and day-to-day operation of your cluster. Although this point is trivial at some sites, it can be a nightmare at others. Before you even begin to think about deploying MSCS, you need to ensure that your site can run TCP/IP as the only transport. You can save a lot of grief by testing client to server, NetBIOS over TCP/IP (NetBT) connectivity with the NBTSTAT utility before you start digging into MSCS. If you can't verify NetBT connectivity, you have bigger problems you need to address (for information on using NetBIOS over TCP/IP, see "Related Articles in Windows NT Magazine," page 165).
Most enterprise TCP/IP connectivity problems revolve around name resolution, so you will also want to be sure that you configure your existing NT servers and clients to use the Windows Internet Naming Service (WINS) for NetBIOS name resolution and Domain Name Server (DNS) for host name resolution. (For information on WINS and DNS, see "Related Articles in Windows NT Magazine," page 165.)