Macs and NFS can coexist

by Joel Snyder for MacWeek (Editor: L. Haymann)

There's more than one way to link a Mac. If you want to network workstations running NFS (Network File System) to Macintoshes, there are three.

NFS was developed by Sun Microsystems to bind together clusters of their Unix- based workstations. NFS has become so popular that it's now available for every major computer, from Macintoshes and MS-DOS PCs up to multi-milllion dollar IBM mainframes.

Like AppleShare, NFS uses both server and client systems. The language is also similar: AppleShare advertises volumes which Macintosh users access via the Chooser; NFS exports file systems for client users to mount on their workstations.

There are three techniques for bringing Macintoshes and NFS together. Macintoshes can run an NFS client application, similar to Apple's AppleShare, which let them mount NFS volumes on a Macintosh desktop.

At the other end of the solution spectrum, an NFS server can also run Appletalk's AFP (Appletalk Filing Protocol) server software, which lets Macintoshes mount NFS volumes as if they were AppleShare volumes.

The middle ground solution include NFS-to- AFP gateways, which translate from NFS protocols to AFP protocols. Because Apple's Macintosh System Software includes AFP client software, managers can integrate AFP servers, such as Apple's AppleShare, into Macintosh networks without adding any software to the Macintosh clients.

Each of these solutions has its own pluses and minuses. The best solution for any environment depends on the exact configuration: how many Macs and how many NFS systems. If a few Macs need to access many NFS servers, changing the software on the Macintosh is cheaper and faster than changing the software on the NFS server. On the other hand, if lots of Macs need to use a few NFS servers, concentrating on the NFS server is a good use of time and money.

The Wollongong Group (415/962-7100) and Intercon Systems (703/709-5500) have been battling over the NFS client market for several years. Wollongong's Pathway Client NFS ($295) and Intercon's NFS/Share ($295) offer the same basic functionality: mount NFS-exported file systems onto Macintoshes.

When the number of NFS servers is far greater than the number of Macintosh clients, NFS client software for the Mac is the solution of choice. Anne-Marie Gallegos, at Lockheed Missiles and Space Co. picked Wollongong's Pathway Client NFS to link a single Quadra 950 to Unix systems from Sun Microsystems, Silicon Graphics, and supercomputer maker Convex Computer.

Lockheed chose NFS client software for the Macintosh to replace cumbersome TCP/IP file transfers between Macintosh and Unix systems. Gallegos was impressed by the Chooser interface which makes mounting NFS volumes only a little more difficult than mounting AppleShare volumes: "the software was very easy to install, and the interface was very intuitive."

At the Aluminum Company of America (Alcoa), NFS was installed on over 100 Macintosh systems as part of their open systems strategy. "Alcoa believes in the OSF (Open Software Foundation) direction," Sue Zapancic notes, citing a network spanning five continents. "We have the most complicated environment in the world, and we're trying to do things on a global basis. We see NFS as a step towards OSF's DFS (Distributed File System)."

Alcoa uses both Wollongong and Intercon NFS client packages on their Macintosh systems, bringing together over 1000 MS-DOS systems and 15 Unix-based NFS servers located all over the world.

World Vision, a Christian relief organization in Munrovia, California, chose NFS client software on Macintoshes for a third reason: server overload. World Vision's Unisys Unix servers were too busy to take on the load of additional server software.

"Communicating between servers and desktop systems was a priority," said World Vision's Larry Dill, "But we wanted to keep our servers as clean as possible, so we chose NFS client software on Mac, DOS, and Windows." Dill thinks that the burden of installing NFS on each machine was outweighed by the Mac-like user interface of the NFS client software. "Management has not been much of a headache for us."

Wollongong recently announced V2.0 of their Pathway Client NFS software, which includes several user interface improvements. Intercon has been shipping V1.3 of NFS/Share for several months. Both Pathway Client NFS and NFS/Share allow the user to customize NFS parameters such as packet size and security settings.

Pathway Client NFS uses the Chooser for parameter management, while NFS/Share options are set at software installation time using custom installations through the standard Macintosh Installer.

Neither Pathway Client NFS nor NFS/Share do anything to help Macintosh users access printers on systems which are also NFS servers. However, Pathway Client NFS does offer an LPR (line printer) server, which lets users on remote TCP/IP systems print to Macintosh-connected printers using the TCP/IP LPR/LPD (line printer/line printer daemon) protocols.

For environments where the Macintoshes far outnumber NFS file servers, adding AFP capability to the NFS server makes more sense. Apple Computer, Digital Equipment Corporation, Helios USA, Information Presentation Technologies, Inc., Pacer Software, Inc., and Xinet Corp. all offer AFP server software which can be used to link Macintoshes into an existing NFS network.

These companies support most popular flavors of the Unix operating system as well as Digital's OpenVMS operating system. (See table for details on who supports what.) These servers also help with the printing problem, by serving printers attached to the NFS servers to Macintosh clients using AppleTalk's PAP (printer access protocol).

Managers of large Macintosh networks prefer to use AFP server software on NFS servers because no additional training is necessary for Macintosh users. AFP server volumes all look the same in the Chooser, whether they're from AppleShare servers or NFS servers running AFP server software.

Gary Witt, Network Manager at magazine and book publisher Meredith Corporation, chose Helios USA's EtherShare on Unix for his mostly-Macintosh environment: "I could have used NFS on the Macintosh. But AFP was better because I can call a computer store and buy 40 or 50 Macintoshes, and they all can access the server without me having to install additional software." Cayman Systems Inc. (617/494-1999) brings NFS services to Macintosh clients using a standalone gateway. Cayman's GatorShare ($995) software acts as a translator between NFS and AFP.

GatorShare makes NFS volumes appear as normal AFP volumes in the Macintosh Chooser. Users can mount the gatewayed file systems without knowing whether they originate on NFS servers or AFP servers.

Gatorshare runs on

• Cayman's Gatorbox EX ($3495, Ethernet-to-Ethernet Router/Gateway),
• Gatorbox CS ($2795, LocalTalk-to-Ethernet Router/Gateway), and the
• Gatorstar GX ($3895, LocalTalk Repeater/Ethernet Gateway) products as an

Gatorshare offers a cost-effective way to add NFS-to-AFP translation to an existing Cayman router or gateway.

Cayman offers GatorShare as a solution for environments where up to 20 Macintosh users need to access NFS file systems.

Cayman also offers GatorPrint ($495), an LPD-to-PAP gateway.

The GatorPrint gateway lets Macintosh users select printers using the Chooser which are accessible through TCP/IP's LPD (line printer daemon) protocol.

Terry Diemer at Silicon Graphics, Inc, (SGI) uses Cayman's GatorShare to link Macintoshes and SGI Unix-based workstations.

Diemer is pleased that GatorShare is so non-intrusive: "It works, and they didn't make us put any software anywhere but the Gatorbox," Diemer notes, "which keeps GatorShare easy to manage."

GatorShare is the only standalone gateway for translating between NFS and AFP, but it's not the only possible solution. Most of the AFP server products listed in the table can also act as gateways betwen NFS and AFP.

For example, VAX running OpenVMS could act as a gateway for multiple Unix servers by mounting the NFS volumes as a client and serving them using Digital's Pathworks for Macintosh software.

Information Presentation Technologies' Partner can take things one step further. It acts as both an AFP server and an AFP client, which means that it can do bi-directional translation between the AFP and NFS worlds.