Installing Microsoft Cluster Server

Installing Microsoft Cluster Server (MSCS) software is straightforward and simple. Notice that I said the server software, not the cluster itself. Installing the cluster is a more difficult task because cluster is more than software: It's a carefully assembled collection of hardware and software that's part of your high-availability computing environment. This article will help you understand that the difficult part of installing MSCS is the preparation. Preparing your system for MSCS takes a lot of planning and hardware configuration. In addition, MSCS has day-to-day administrative rules that you must follow or you'll need to reinstall the MSCS software. I'll walk you through the process of planning for, preparing your system for, and installing MSCS. Let's begin with a look at MSCS's software requirements.

The Software
Because MSCS runs only on Windows NT Server, Enterprise Edition (NTS/E), you must first install two NTS/E systems, which function as the basic building blocks for a failover configuration. In fact, if you attempt to run the Cluster Setup program on a system that doesn't have NTS/E installed, Cluster Setup only presents the option of installing the Cluster Administrator program. As you can see in Screen 1, the NTS/E base CD-ROM looks similar to the CD-ROM for NT Server 4.0. The NTS/E CD-ROM includes the binaries for Alpha and Intel processors, clients, and support directories. The CD-ROM also includes Service Pack 3 (SP3).

Screen 2 displays the directory of the second, or component, CD-ROM. The component CD-ROM contains the additional components of NTS/E: MSCS, Microsoft Message Queue Server (MSMQ), Microsoft Transaction Server (MTS), and a support directory for these products. The CD-ROM also includes Microsoft's Internet programs: FrontPage, an upgrade to version 3.0 of Internet Information Server (IIS), Active Server Pages (ASP), Microsoft Index Server, NetShow On-Demand Server, and NetShow Live Server.

Configuration Rules
As you plan your MSCS installation, you need to be aware of these two preinstallation and configuration rules: Cluster nodes must be running NTS/E, and cluster nodes must belong to the same NT domain and cluster. The MSCS documentation does not mention that you can install cluster nodes in a domain controller-member server configuration, which means that a cluster member can function in any domain role. I prefer to install cluster nodes as servers and not domain controllers, which reduces the overhead on these systems. (When a server is a domain controller, the entire user accounts database goes into a nonpage pool.) Make your domain-role decisions carefully, because to change a server to a domain controller, you must reinstall NT. For flexibility, I prefer to install NTS/E systems as member servers or as a Backup Domain Controller (BDC)-member server combination.

Although you can format the node's system drives with the FAT file system, you must format the shared storage with NTFS. If you use NTFS on your system drives, you might want to consider the following strategy. Install two copies of NT. One copy is for everyday use, and the other copy lets you boot the system and still access the system drives. Installing two copies of NT will more than pay for the purchase price if something goes wrong with your production copy. You can also use the alternative copy to back up and restore systems. Doing so lets you make a file-level backup that eliminates concerns about changes to open system files on your production copy of NTS/E.

If you install and boot under the secondary copy of NT be very careful about accessing the shared disks. Since NTFS isn't a cluster file system the shared disks should only be accessible by one system at a time. Accessing the shared disks simultaneously from multiple systems will cause disk corruption. MSCS avoids this issue by using the Cluster Disk Driver to limit disk access to one node at a time. While this is a simple solution, if you are like most of my clients, you look forward to Compaq's release of their cluster file system and distributed lock manager that will allow shared access to clustered storage.