[ Go to February 1997 Table of Contents ]|
-- by Tom Henderson
The horror of it. That's how some enterprise administrators-and most end users-react when they must move from one complicated file system to another, or migrate data between disparate file systems. Issues like different naming conventions and dissimilar file formats are the stuff of a network admin's nightmares.
But don't lose hope. File system advances are making interoperability more feasible and easing migration headaches. We've come a long way from the dark days of DOS to Microsoft's forthcoming Distributed File System (download a preview of DFS from http://www.microsoft.com/windows/common/a2263.htm)
For years, Mac, UNIX and OS/2 users thumbed their collective noses at DOS. And for good reason. At first, DOS offered no subdirectories. And its ludicrous 8.3 filenaming convention was a major sticking point later inherited by Windows 3.x. But don't blame Microsoft-the 8.3 filename system was baggage carried over from the days of CP/M and Digital's RT-11 operating system.
If you managed to dodge the Windows bandwagon until the release of Win95, you're living in a filing system fantasy-land. Like you, I'm spoiled by filenames like My Windows Magazine Column for February 1997, rather than COLFEB97.DOC. Of course, Mac, UNIX and OS/2 users have enjoyed long filename support for years.
NetWare, the leading server operating system (yes, still ahead of NT Server), also offers long filename support. Novell was arguably the first vendor to get naming conventions right by supporting not only 8.3 filenames, but also Mac, POSIX and UNIX via what Novell termed "name spaces."
You can activate NetWare's long filename support by adding the line load os2.nam. Then assign the OS2 name space to each NetWare volume. Most NetWare DOS utilities will still try to truncate the long filenames to 8.3. To compensate, simply use the Windows GUI from Windows NT or 95 to enforce the filename length capability.
The interoperability offered by NetWare has fostered connections to central resources such as file and print services, mail communications and higher-level data interchange.
Share and share alike
Data interchange means common file formats. At some point in mid-1994, the de facto file formats changed. Around that time, the lingua franca for word processing documents shifted from WordPerfect and simple ASCII text to Microsoft Word. Likewise, spreadsheet programs began to abandon Lotus 1-2-3 version 2.x in favor of Excel. Database file formats still hover around the DBF format advanced by Ashton-Tate, then Borland, Fox (now owned by Microsoft) and Nantucket Clipper (acquired by Computer Associates). Another shift happened when publishers dumped ATEX for Quark and PageMaker.
Some file format intermediaries have also arrived. Adobe Acrobat gained popularity because it provided a method to view and develop content across multiple platforms. Corel's Envoy format offers some of the same ideals as Acrobat, but has suffered by being handed off like a hot potato from WordPerfect to Novell and now to Corel.
Network file systems
Despite the advances in file formats, linking file systems transparently to users remained difficult. To compensate, Sun Microsystems invented the Network File System (NFS)
Under Sun's concept (sanctioned by the Internet Engineering Task Force), each NFS server contains a list of directories that can be "exported," another name for a "share" in Microsoft terminology. Each server that exported directories could, in turn, have a client that mounted the directory structure somewhere under the client filing system's root directory. In effect, users would think a remote file system actually existed on their local system.
Another filing system, the Andrew File System (AFS), was invented to extend Sun's resource sharing metaphor along other lines. AFS, originally conceived at Carnegie-Mellon University, was commercialized by Transarc Corp. (now owned by IBM)
While NFS requires DNS (the TCP/IP Domain Naming System) to resolve locations, AFS initializes and resolves the location specifics on its own. AFS eventually became the ONC/DCE Distributed File System (DFS)
Microsoft joins the party
Microsoft has taken the same acronym, DFS, to describe its new resource-joining software. DFS runs strictly under Windows NT Server 4.0, though support for it is built into NT Workstation 4.0.
The Microsoft DFS is currently less ambitious than AFS/DFS-it can only tie together NT and NetWare Servers. In this version, DFS ignores UNIX, OpenVMS and IBM filing systems. Nonetheless, DFS represents a solid start at a distributed file system.
To understand why, take a look at Microsoft's Domain Services Manager for Net-Ware (DSMNW). It allows NT administrators to manage NetWare in an NT-dominated environment. During DSMNW's installation, NetWare 3.x's bindery database is digested into a target NT server, and the bindery no longer exists in those servers except to feed the NT Server NetWare Gateway (NTGATEWAY)
Microsoft DFS, by contrast, is much gentler. Instead of requiring (in)digestion of a NetWare bindery, DFS uses an NT-NetWare gateway to present users with what appears to be a single set of resources, but without moving information about those resources from NetWare to NT. The result, which adheres to Windows NT's security model, is displayed as a simple set of hierarchical folders. By contrast, in the current pre-DFS model, the Network Neighborhood is divided into Microsoft Network and Novell resources. To find a specific file, a user must drill down through layers of complicated servers, volumes and folders.
While promising, DFS only supports 32-bit Windows clients, leaving Windows 3.x users out in the cold. And since DFS hadn't been completed for general release as of this writing, its true speed is unknown. However, in theory, DFS access should be just as fast as creating shortcuts to folders.
A heads up to Novell GroupWise adminstrators: The NetWare 32 client for Windows NT contains new NetWare Administrator software that is potentially incompatible with GroupWise 5.0 because of DLL changes. To be safe, stick with the administrator software that came with GroupWise when you manage that application.
And for those dabbling with beta software, look out! An Office 97 beta release reminded me, the hard way, not to use unreleased software on my production system. After the suite went sour, I had to flatten my Compaq LTE 5200 notebook's hard disk and rebuild it from scratch. I've gone back to using Seagate's WinInstall (http://www.sems.com/Products/East/
Well, at least I got to start with a clear file system.
Contributing Editor Tom Henderson is vice president of engineering for Indianapolis-based Unitel. Contact Tom in the "Enterprise Administrator" topic of WINDOWS Magazine's areas on America Online and CompuServe, or care of the editor at the e-mail addresses here.