Microsoft WindowsServer 2003 RC2

Many more companies are looking at clustering these days, because it's simple to implement and is such an easy way to provide a stronger guarantee of uptime. This is especially true of an operation that has to run almost continually, with the in-house IT team on-site for up to ten hours per day. It's also particularly pertinent, considering the availability of today's lower-priced SANs (Storage Area Networks).

The Network Load Balancing (NLB) facility has been improved too, to allow for virtual clusters. These let you configure different port rules for different cluster IP addresses, where each cluster IP address corresponds to a website or application being hosted on the NLB cluster. It's also used to filter out traffic sent to a specific website or application on a specific host in the cluster, and finally, to choose which host in a cluster should be used to service traffic sent to a specific website or application being hosted on the cluster.

File system

In the file system area, there has been a number of improvements. If you have XP clients, you'll certainly want to enable Volume Shadow Copy. This takes over a fixed percentage of your hard disk space and uses it to seamlessly create backup versions of files as they are used. There is a time schedule applied to this, so you could have it run every hour or three times a day during the working week, for example. If you suddenly need to go back to a previous version of the file, just choose the appropriate Previous Versions facility in the Windows Explorer on your XP client and it will automatically show you all the previous versions that have been stored away.

Given that accidental deletion, or modification followed by file save, is an extremely common reason for people losing data or having to retype sections of documents, this is a major step forward for ease of use, because it puts the recovery facility right onto the desktop of the user concerned. They no longer have to pester the IT department to recover a file from backup.

Other changes are aimed at higher-end customers. For example, in Windows 2000 each SAN hardware vendor had to provide their own proprietary set of APIs for managing their hardware, which made uniform management and control difficult. With Virtual Disk Service in Server 2003, Microsoft has written an interface layer that allows for a uniform way of working with these SAN systems and therefore has enabled the writing of a built-in Volume Shadow Copy Service.

Since Shadow Copy is now part of the OS function, a raft of applications can take advantage of it in a uniform way, including future versions of Exchange. With a Shadow Copy, you can split a mirror into two parts and back up one part while the other still runs. At the end of the backup process, the two halves are automatically re-synchronised and joined back together.

For 64-bit computers, there are no Master Boot Record files on the hard disk to indicate the disk partitioning. Instead, they've moved to a GPT (GUID Partition Table) arrangement that benefits from redundant primary and backup partition tables for better partition integrity.

The Distributed File System has been improved to allow more intelligent routing of file requests, based on the site topology defined in AD. And the File Replication Service allows you to dump unnecessary replication traffic and to compress the traffic on the wire, therefore improving throughput. There are new file system filter APIs too for anti-virus applications to use, and a faster defragmentation tool.