The server magic of DFS

Office WatchLast updated: 17 July 2018

A little used feature in Windows Server will let you assign a fixed path to a folder even if you later change the server setup to a new physical location

“You said that network administrators didn’t have to use drive letters assignments to network shares but that’s not true. On our network we have shared documents linked via drive letter S: – that’s because sometimes we have to change the server storing the shared documents.

If we didn’t use a mapped network drive we’d have to tell all our users to switch from //Paul server to the //Ringo server – as it is we only have to reassign drive S: and the users don’t realise there’s been a change.” Ronnie W.

We don’t normally delve into server matters but Ronnie (and other network admins) deserve a response after our aside in a previous article.

Windows Server does provide a way to have ‘fixed’ network share names that can be re-assigned to a particular server share as required. It does away with mapped network drive letters and is even easier to manage.

The feature was called Distributed File System (DFS) and is now called DFS Namespaces from Windows Server 2003 R2. Whatever it’s called, it is available in Windows Server 2000, 2003 and 2008 plus Small Business Server 2003.

You’re forgiven for overlooking this server feature, like many server options its not well promoted nor explained. In this case even the name seems imposing. When you start reading Microsoft’s blurb about “state-based, multimaster replication engine” you can feel your eyelids drooping.

Here’s a simple example of a home network with Windows Server 2003 (unusual I know but it’s for the sake of simplicity). There are shares for media played throughout the house one for Music and another for Video and another for Books.

Normally you’d have fixed shares to the computers that have each folder. For example //John/Video or //George/Music (we’ve followed Ronnie’s ‘Beatles’ naming convention for servers ).

But what if you need to change the location of the video files? Maybe the //John server has run out of room or you’ve decided to switch computers. A common experience these days is to switch from a computer serving files to a network attached storage (NAS) box.

Without DFS you need to change each computer on the network from //John/Video to //Richard/Video with all the complications that entails. Or re-configure the mapped network drive on each networked computer.

With DFS there’s a virtual share or link on the Pete server such as //Pete/Video which points to wherever the music files are currently being stored. All you have to do is change the server setting (eg so //Pete/Video points to the new location //Richard/Video in DFS ). The change is immediate for the whole network and does not need any re-configuring of the client computers.

So on our home network each computer would permanently point to:

//Pete/Music

//Pete/Video

//Pete/Books

Only the DFS feature on the //Pete server knows where the files really are and points computers to the right place seamlessly and automatically.

There’s a lot more to Distributed File System but that’s the basic feature and very useful it is too.