As Windows 2003 Server R2 release time draws closer, Redmond is getting more and more detailed with us on what’s really going to be included in the new release. Turns out those 120MB are going to include a whole bunch of stuff. One lesser known new feature will be a remote site management capability. Dubbed Branch on all the marketing slides, this is an installation of Windows Server that’s optimised for branch office workloads.
Redmond says it’s done significant customer surveys, studies, and vivisectionist investigations and determined that branch office applications represent a surprisingly huge part of the IT landscape. According to Microsoft, fully 55 per cent of medium- and large-enterprise staff are in branch offices, and that between a quarter and third of all installed Windows servers are in remote sites. Turns out every McDonald's has a server, and every Jack in the Box has two.
So the concept of Branch was born. Microsoft is quick to point out that this does not represent a new SKU of Windows 2003 Server. Although the company flirted with this idea, the Standard Edition seemed well suited to the task, with optimisation concentrated on specific new technologies and configuration tweaks.
On the surface, Branch is designed to incorporate a fairly basic set of features, including DNS/WINS; DHCP; SMS (agent/secondary site config); a MOM (Microsoft Operations Manager) agent; secondary Terminal Services capability; ISA (Internet Security and Acceleration, for HTTP caching, local firewall and site-to-site VPN); and Windows Storage Server for Windows storage appliances.
Microsoft is partnering with some OEMs to build Branch-based appliances, but anyone with R2 can build their own Branch servers based on Windows 2003 Server Standard Edition. If this seems (rightly) to be far more complex once you get into line of business applications, don’t fret; Microsoft has made a guide available on the Web site for building Branch servers and designing Branch-based remote architectures.
Much of the potential complexity comes from a key new Branch technology, which is a serious revamping of DFS (Distributed File System), mainly because managing file services at the branch office has always been a pain. Merely backing up data is agonising; total consolidation management has always been pretty much impossible with native OS tools. Local backup is the only way to cover your posterior, but even reconciling those changes to a hub site on a scheduled basis is difficult.
The new DFS is far more flexible and fast than its predecessor, if I can believe the demo tests I’ve just seen. The new DFS is sexy in all kinds of ways. First, the new management interface (an MMC, Microsoft Management Console, snap-in) is not only easy, it’s fast. You can manage DFS over multiple topologies (hub-and-spoke, meshed, whatever), manage bandwidth utilisation, and manage scheduling. You can even mix these tasks; for example, you can schedule specific bandwidth utilisations for certain times -- which can be huge for many operations.
DFS performance is helped with both a brand new replication engine as well as a new compression scheme, dubbed remote differential compression (RDC). The new replication engine can stack-rank nearby servers for dynamic and transparent access request management — in any topology you’d care to choose. This is doable down to hundreds of levels of failover (even though Microsoft says that 380 levels of failover is the limit).
The new RDC compression scheme is based on MIT work, and it achieves not only high compression rates but excellent bandwidth management via smart change management. In replication scenarios, RDC will update only the changes between two replicated files, again based on fairly tight file restrictions constructed during DFS setup. The combination means DFS is now a powerful and fairly fast means of connecting branch offices to home site hubs. You’ve still got the question of whose changes take precedence when updating a file, but if this is a serious issue for you, Redmond recommends using SharePoint collaboration services as they’ll drop full check-in/check-out version control on top of this.
Branch also includes a nifty new print manager, specifically designed to manage remote printers. Install new hardware, and administrators can push those printers to specific sets of users with a single mouse click.
Overall, Branch is a solid concept if you think of it as a caching server designed to keep a remote office running whether or not there’s a WAN link. For basic data services, this seems to work well. For specific applications, however, there’s more work to be done. Database replication, for example, requires a whole other level of administration on top of DFS in order to function.
Microsoft knows this and says that this release of R2 Branch will concentrate solely on File, Print, and Active Directory Services. Other apps are considered “line of business” and Branch will be addressing them sequentially going forward. Fortunately, database functionality is at the top of the list.