Unix in sheep's clothing
Syntax TotalNET Advanced Server turns your Unix server into NT, NetWare, or AppleTalk servers
Finding a means to connect your PCs to a Unix server is hard enough. What happens when you have a heterogeneous network of AppleTalk, NetWare, and NT all at once? Guess what? Syntax has an elegant solution. (1,600 words)
Here's a product that turns your Unix system into a file and print server for any Windows or Macintosh desktop. It introduces NetBIOS, NetBEUI, IPX/SPX, and AppleTalk services at the protocol level directly into the Unix operating system. More than that, Syntax has ported this product to many leading Unix platforms: AIX, Solaris, HP-UX, and IRIX, and to different versions of each OS. This single product can allow your cacophony of desktops to chime together in near-perfect harmony, all using the same printers and sharing file systems.
File sharing is one of the oldest reasons for networking. It started out as a means for multiuser applications to communicate between users using files as temporary storage. It then moved towards centralizing a disk system for the network such that it could be managed and monitored more easily. Both disks and printers were fairly expensive at one time, so creating a central repository made sense. Server-based applications then started communicating with the network clients with smarter code such as semaphores, mailboxes, and sockets.
Windows and NetWare have been sitting in this position for well over a decade. On the Unix front, systems were sharing disks with NFS; Sun's PC-NFS brought the idea of Unix-to-PC resource sharing to the forefront. Throughout the late '80s and early '90s, there were quite a few small companies doing very well creating (PC)NFS-based software and TCP/IP protocol stacks for the Windows environment.
Since the arrival of Windows 3.11, when TCP/IP became the default network protocol for Windows for Workgroups, these companies have either merged or been acquired by larger, more buoyant vendors. In recent news, FTP Software Inc. -- one of the leading forerunners and most technically competent members of this group -- was acquired by NetManage Inc., a primary competitor, signaling an imminent end to the independent PC TCP/IP and NFS vendor market. In fact, with its NT Services for Unix, Microsoft, the biggest competitor of all, may obliterate all competing products.
Syntax has survived by partnering with Unix vendors and by supporting a wide variety of the competing network operating systems you find in heterogeneous networks the world over. The three separate products to support LAN Manager, NetWare, and AppleTalk were long ago combined into one. Syntax has kept up with the times and converted its management interface to the Web. At the same time, it has stuck to its Unix roots, with command-line programs that perform the same functions as those that can be initiated via a Web interface. It provides native support for the various protocols mentioned above.
TotalNET Advanced Server's structure is based on realms. Each realm is particular to a type of NOS, and although each provides separate functions, they can all can be managed through the same interface. There are three primary realms: the AppleTalk realm, the NetWare realm, and the LAN Manager-NT-OS/2 realm -- which consists of all the NOSs that use the NetBIOS system.
A recent installation of TAS was fairly simple using the standard Solaris pkgadd program. It was all automatic, and the system didn't even need to reboot despite the low-level drivers that were installed. Apparently, installing TAS on AIX or IRIX does require some basic manual driver configuration, which is detailed in the installation guide.
In addition TNAS has management modules known as spheres. Each realm is managed through a sphere, but several common components like user accounts, passwords, file permissions, network transport protocols, system status, and documentation are placed in separate spheres as well. In other words, you don't have to create three different user accounts to support the three different realms, and components that correlate across the realms can be addressed through common services.
At the command-line level, the same rules apply, though you can also directly access print and file functions for each realm separately. The command-line interface is designed to work well in script files, requiring little additional input after the command string itself. While this isn't a significant worry, it does make writing scripts using these commands much cleaner.
Since the protocols, file systems, and printing systems differ across the three realms supported, TAS keeps shadow files and directories to support the different file systems. There are two common shadow files. One is called .tnatr:intf, and stores file attribute information that isn't supported under Unix but is available in the foreign file system. The other file, called .tnatr:fnmap, is a file name mapping system that handles the issue of lowercase and uppercase names under the foreign file systems.
The file structure of the Macintosh is quite different from PC or Unix files in that it has a data fork containing the raw data of the document or program and a resource fork providing loading instructions, graphical information, and application information. This has caused confusion to many PC network administrators not familiar with the reason or importance of the resource fork. TAS keeps pairs of files for each Macintosh file with resource forks in a Unix directory called .tnatr:reso- fork to match the Mac volumes.
AppleTalk itself started out as a different protocol. The underlying transport protocol called the Datagram Delivery Protocol (DDP) is conceptually similar to Novell IPX, but of course the two aren't compatible. Both are self-configuring network protocols, require little information other than a naming scheme for their area of influence, and don't route very well. Although Macs have moved on to MacTCP environments, AppleTalk is still often used. AppleTalk 2 networks (version 1 nets are pretty much obsolete) are split according to zones.
To deal with these realm specifics, TAS provides commands for file manipulation as well as DDP and AppleTalk management. For example, you can list and modify file attributes, create, modify, and delete Macintosh folders and volumes, discover the AppleTalk zones on your net and probe them for information, and even go as low as to read the contents of DDP packets.
The NetWare realm allows you to create and manage NetWare volumes as well as manage the network virtual terminal (NVT) connections to the server. The system installs IPX and SPX on the raw Ethernet driver. Most of the features of volume management for NetWare are the same as in 4.11, albeit in different clothes.
The NetBIOS protocol used by NT, OS/2, and LAN Manager remains the same across all three platforms. In fact, plain NetBIOS is used over IP for the most part, although you can install the NetBEUI protocol as an adjunct if your PC LAN server or OS/2 systems only speak this. Sharing resources using NetBIOS is simple -- just designate the workgroup name.
All in one
TAS is one of the few products that can support all three major PC networking systems on different Unix systems. The file systems and printers look as natural as if they were actual PC-based servers. The big problem with porting one environment to another is that you never know what tiny change in the code from the original might cause a breakdown in services. In order to get early networking software for PCs to work on ill-equipped DOS, notorious kludges were created. With newer versions, most of the hacks are gone, along with DOS (at least the networking part). With Unix servers, you might even enjoy the advantage of a true multiuser environment, where a lock-up of one network user's application doesn't affect that of another (unless it interferes with the low-level drivers).
The problem associated with using TAS is that the level-one tech support people employed by many PC application vendors claim that the non-standard environment of TAS is the root of all evil. Since it's not a direct Microsoft implementation -- and worse, it runs on Unix -- it's quickly written off as the source of any and all problems. Because vendors don't presently support such an environment, you may be out of luck when trying to get outside help.
About the author
Rawn Shah is chief analyst for Razor Research Group covering WAN and MAN networking technology and network-centric computing. He has expertise in a wide range of technologies including ATM, DSL, PC-to-Unix connectivity, PC network programming, Unix software development, and systems integration. He helped found NC World magazine in December 1996, and has led the charge to the deployment of network-centric computing in the corporate world. Reach Rawn at firstname.lastname@example.org.
If you have technical problems with this magazine, contact email@example.com