Microsoft WindowsServer 2003 RC2

Some companies were forward-looking and deployed AD-enabled applications. In other words, they specifically used AD as a repository for information for some of their line-of-business applications. This had a significant number of pros and cons, the worst being that you had to be careful about where you replicated the information to around your organisation, and try and prevent traffic storms arising. With the new AD Application Mode (AM) of working, you can partition off such application information within AD and therefore have much better control. AD/AM will probably ship as an add-on after Server 2003 ships.

Managing group policies - and indeed general management - was a pain in W2K AD. Many system administrators found their right mouse button was worn out before their left, such was the reliance on right-click context menus. There have been nowhere near enough improvements in this area, but those made are well worth having. The ability to store queries and to reuse them might not sound much, but it does allow system administrators to save standard queries for commonly used objects or searches in their AD designs. The forthcoming Group Policy Editor will also help to unravel what's going on in the AD design and implementation.

A boon for those system administrators who have to manage a wide area network is the removal of the need for Global Catalogue (GC) servers on remote sites. With W2K, you can only be authenticated for login by a GC server, which meant having one on each site to protect you from inter-site network failures. But putting GCs on remote networks meant that all the AD GC traffic had to go down that wire, even if it was for stuff that was never really used. With Server 2003, security credentials can be cached by a Server 2003 in a remote office, therefore alleviating the need for a remote GC.

Another big win is the ability to pre-load an AD Controller with AD information from a central source, and to do so via tape, CD-R or some other backup. In other words, if you want to bring up an AD server on a remote site on the WAN, you can install Server 2003 and then load its AD information from a backup sent to you from the central IT organisation. It saves the need to replicate the potentially large AD information over what might be a slow link. Again, this is a clear example of how Microsoft has learned from the real-world deployment of AD in Windows 2000 AD.

Clustering

In Windows 2000 Advanced Server, you were limited to a four-way cluster arrangement. With Server 2003 Enterprise Edition, the maximum limit has been raised to eight-way clustering and, with the Datacenter Edition, this is just the minimum. Not only that, it has been made considerably easier to manage, implement and deploy, with no reboots required. The preferred way of working is N+I, where you have N active nodes and I spare nodes, rather than for a fully active cluster. This is still true for the forthcoming Windows Exchange Server 2003 Titanium Edition, which has the same limitations for cluster failover as the existing Exchange Server 2000 and will require a complete re-architecture to overcome.

Clustering is now properly integrated into the AD environment, including the publishing of a virtual computer object that allows for AD-aware applications to talk to the virtual object and therefore to the cluster.

Finally, you don't need to have a shared filespace area available for the cluster to communicate through. There's a new quorum resource called Majority Node Set, which allows server clusters to be built without using a shared disk as the quorum device. As a result of this new quorum mechanism, additional cluster topologies can be built; for example, server clusters with no shared disks. Majority Node Set also makes it easier to build and configure multisite, geographically dispersed clusters, which will be of interest to those running on large WAN network topologies.