NFS Servers for Windows NT

Which NFS server for NT solves your connectivity problems?

As Windows NT becomes more prevalent in the data center, users are demanding connectivity solutions between NT and other client/server OSs. UNIX, AS/400, VMS, and other non-Windows OSs must share files with NT-based systems, and NFS provides the connection. NFS might not be the fastest or most secure solution for file sharing, but it's available on almost all platforms, including UNIX and Linux. In addition, you can use WebNFS from browsers and Java applications instead of FTP or HTTP to transfer files. In our increasingly Web-centric world, using a combination of NFS and WebNFS when you need to make files accessible to the widest possible audience makes sense.

Three types of NFS products are available for NT—servers, clients, and gateways. UNIX and other non-Windows OSs use NFS servers for NT to mount shares and access resources on an NT server. NFS clients let Windows computers access NFS servers. NFS clients also support all basic I/O operations, such as reading, writing, and setting file attributes, across multiple server platforms. NFS gateways let Windows clients access NFS servers on non-Windows OSs. Windows clients don't need to connect to the NFS server, so they don't require client software on their Windows desktops. You can set up NFS gateways on an NT server to access the NFS server, which lets Windows clients use resources on the NFS server. NFS gateways convert Windows clients' file-access requests to NFS calls to the NFS server and return the results to the Windows client.

We focus on using NFS products to access NT servers from non-Windows OSs, so we examine only NFS servers for NT and consider each product's ease of integration, functionality, usability, and manageability. We compare six NFS servers that run on NT—Hummingbird Communications' NFS Maestro Server 6.1.1, NetManage's InterDrive Server 2.0, Microsoft's Windows NT Services for UNIX 1.0a, Intergraph's DiskShare 4.01, Frontier Technologies' SuperNFS, and Xlink Technology's Omni-NFS Server.

We installed each product on single- and dual-processor servers with multiple NICs running NT Server 4.0 Service Pack 5 (SP5). Our test clients included a Sun Microsystems' UltraSPARC 5 workstation running Solaris 7, a Dell Precision WorkStation 410 running Solaris 7 for Intel, and a variety of UNIX and Linux clients on a local network. The UNIX and Linux clients used Network Information System (NIS), and the Solaris clients used NIS+.

NFS Maestro Server 6.1.1
The documentation for NFS Maestro Server is excellent and provides for a straightforward setup. You insert the CD-ROM into your drive, click Install Maestro Server, and follow the prompts. Alternatively, you can run the msetup.exe (not setup.exe, as is common with Windows applications) program from the CD-ROM. NFS Maestro Server is the only product in our review that doesn't require you to reboot when the installation completes.

In addition to the NFS server, the NFS Maestro Server package includes a SOCKS client, an Inetd daemon, NIS, and several useful utilities, so you don't need to install other packages to gain the functionality that these services provide. You use the Inetd daemon to start and stop common daemons, such as bootp, telnetd, ftpd, fingerd, tftpd, lpd, timed, tnamed, and Xstartd.

NFS Maestro Server has two Control Panel applets for administration—Hardware Compatibility List (HCL) Inetd for line printer daemon and other services, and HCL NFS Server for the NFS server. Some of the other products we reviewed add services or protocols to the Control Panel Network applet, but NFS Maestro Server doesn't. NFS Maestro Server provides the Hummingbird Inetd, Hummingbird NFS Server, and Hummingbird Port Mapper services and works with other port mappers. We noticed one minor problem with the HCL Inetd applet. If you don't start the HCL Inetd service and you double-click the HCL Inetd icon, you get a warning message that the service didn't start. If you start the HCL Inetd service and double-click the icon, nothing seems to happen. We had to reboot the computer to start common daemons.

The product offers several options for mapping usernames across UNIX and NT through password and group files or through NIS. You can also select between UNIX and NT styles for permissions. At first glance, the dialog boxes in the HCL NFS Server Control Panel applet are a bit confusing. For example, when you configure the NFS Maestro Server system, the Exported File Systems tab in the HCL NFS Server Control Panel applet includes an Insert button at the bottom of the dialog box, which Screen 1, page 115, shows. You use this button to add directories to the uppermost list box. Typical Windows applications would probably place the button closer to the list box that the button acts on. In the same dialog box, after you select the check box to restrict to specific hosts, you can't clear the check box to enable the access. You must delete all the entries, then clear the check box. You need to read the NFS Maestro Server documentation carefully to avoid these types of problems, but after you set up the product properly, it works almost seamlessly.

WebNFS initially gave us a problem. Although we could see the filenames in exported directories, we couldn't use a UNIX systems browser to read or download the files. After a few minutes, we were able use a Solaris browser to access the files with no changes in permissions or files. The NFS Maestro Server service takes about 1 to 2 minutes before letting you access a resource. We contacted the vendor, who mentioned that this delay is a bug that the company fixed in the 6.2.2 release, which should be available by the publication date of this review.

Printing with NFS Maestro Server is a breeze. You use standard NT mechanisms (e.g., Start, Settings, Printers, Add Printer) to configure printers and export the printers to NFS clients. We easily printed to HP printers from Solaris and Linux machines. However, in our test environment, we noticed a slight delay between when you set up the printer on the NFS Maestro Server system and when NFS clients could access the printer.

The dialog boxes for administering and monitoring NFS Maestro Server are cluttered and might be confusing to the novice user (but are still a major improvement over previous versions). If you have an enterprise environment with several NFS servers, you might want to manage all servers from one system. Unfortunately, NFS Maestro Server's administration tools currently can't perform this function. We also found a 1- to 2-minute delay before we could access an exported directory or printer from clients. The vendor claims that it fixed this problem in the 6.2.2 release. With the exception of these two problems, NFS Maestro Server is easy to maintain and configure.

InterDrive Server 2.0
NetManage acquired FTP Software in early 1999 and plans to integrate FTP's InterDrive Server into its new eN2000 product family. InterDrive Server will still be available as a separate NFS product, so we included it in our review.

InterDrive Server's installation is cumbersome, although the documentation (a Windows Help file) provides adequate step-by-step instructions. After you begin the installation, dialog boxes direct you to the Control Panel Network applet to add a service. If you aren't familiar with adding network services, you might find this step confusing. You must select the drive and directory in which you inserted the CD-ROM and navigate to the srvnti386 folder on Intel-based servers or to the srvntalpha folder on Alpha-based systems. This process adds InterDrive Server to the list of network services, and you must reboot the system.

InterDrive Server sets up four services—a Line Print Daemon (LPD), an NFS file server, NFS users and printers, and a port mapper. You can use NT's standard Control Panel Services applet or InterDrive Server's Server Control application to control these four services. By default, you must start the services manually. To initiate the services during the boot process, don't change the startup to automatic in the Control Panel Services applet. InterDrive Server seems to work properly only when you start the services from the Server Control application. If you want NFS-related services to automatically start on a reboot, you must go to ServerControlSettingsStartup in the Server Control application and move the services you want automatically started to the Active Servers at System Startup list.

When you start the Server Control application, you see four minimized windows: NFS File Server, NFS Users and Printers, NFS Monitor, and LPD Monitor. Each window provides a fairly detailed set of statistics.

Of all the products we tested, InterDrive Server provides the easiest access from WebNFS clients. We didn't observe any errors, and WebNFS clients easily accessed files on the NT server.

When we tried to create new printers from the Server Control application, we got a few application errors. Dr. Watson reported that the problem was an access violation by ctlapp32.exe. Existing printers worked. New printers we created through the Control Panel Services applet didn't result in application errors, but we needed to configure NFS clients to access the new printers.

When we tried to create new exported shares on InterDrive Server running on a dual-processor Dell server, the Server Control application periodically froze. We couldn't add new exported directories and had to close the application and restart it. This problem occurred only on SMP servers and not on machines with single processors. We contacted the NetManage support staff, who provided us with a patch that solved our problem.

Compared with the other NFS servers in our review, InterDrive Server provides a more straightforward set of dialog boxes to set up NFS Server Options, which Screen 2 shows. You don't need to use multiple applications to set up permissions and server parameters.

Unfortunately, InterDrive Server lacks most of the management features you expect from Win32 applications. For example, you can't uninstall the product through a setup program or through the Control Panel Add/Remove Programs applet. You also can't safely start and stop the services from the Control Panel Services applet. In fact, the documentation warns against performing any function from the Services applet. To uninstall the product, you must delete files and clean the Registry. With the exception of these limitations, InterDrive Server is a solid product and adequately provides NT resources to NFS clients.

Windows NT Services for UNIX 1.0a and DiskShare 4.01
Microsoft's Windows NT Services for UNIX includes a licensed version of Intergraph's DiskShare (which Microsoft renamed Server for NFS), a Telnet client and server, and UNIX utilities. Intergraph still offers DiskShare as a separate product. DiskShare and Server for NFS share the same user interface (UI), documentation, integration features, and functionality. Because Microsoft licensed DiskShare from Intergraph, we include both products under one heading.

You install DiskShare and Server for NFS through the standard setup utility. Because we focus on NFS functionality, we installed Server for NFS's modules that relate to NFS services only, not all the features the product includes. You use identical dialog boxes to configure DiskShare and Server for NFS, and you can use mapped usernames and passwords or NIS to authenticate UNIX users. In this respect, both products are identical.

Although Server for NFS is fundamentally the same as DiskShare, you'll find several cosmetic differences with respect to how each vendor arranges the product's utilities. From the NFS server perspective, we like the way that Intergraph groups DiskShare's related programs and utilities in one Start submenu. In contrast, Microsoft distributes Server for NFS' programs and utilities among four Start submenus.

One of the biggest differences between DiskShare and Server for NFS and the other products we reviewed involves how these two NFS servers integrate with NT. When you right-click a folder in Windows Explorer and select Sharing, you'll see the NFS Sharing tab. Screen 3, page 117, shows the creation of a share point called SFUShare. NFS Sharing is well integrated with the DiskShare Control Panel Configuration applet, or in the case of the Microsoft product, Server for NFS Configuration applet. Clicking Modify/View Permissions on the NFS Sharing tab launches the NFS Share Permissions dialog box that lets you easily set global permissions—Read/Write or Read Only. Clicking Configure in the NFS Permissions dialog box opens the Server for NFS Configuration utility (or DiskShare Configuration utility with Intergraph's product). From this utility, you can set Share Options and Server Options. NT administrators use this approach to easily add NFS shares that UNIX clients can access. You can readily configure user and group mappings to convert UNIX-style user IDs and group IDs (GIDs) to NT usernames and groups. The NT usernames can be local usernames or domain accounts. You must copy the UNIX password file and the group file and keep them in the %systemroot%system32driversetc folder. You can also use NIS to map UNIX-style user IDs and GIDs. If you set up an NIS domain, you query for the users on the UNIX systems and map those user IDs to NT usernames.

Both DiskShare and Server for NFS ignore WebNFS clients because the vendors didn't include the WebNFS feature in these products. If you're a WebNFS fan, don't consider either product. However, DiskShare and Server for NFS support all other standard NFS features, including NFS 2 and 3. Overall, we like both products' tight integration with Windows Explorer, straightforward configuration procedure, and usability for mapping NT and UNIX users.

SuperNFS
SuperNFS is similar to InterDrive Server in that both vendors base their product's UI and configuration on earlier NT versions. SuperNFS, however, requires a couple of reboots during installation. You run the setup program from the CD-ROM and reboot the system to install the software. After the system reboots, you must enable the NFS server from SuperNFS's SetupTCP program to add the NFS server and the authentication services. Both services will automatically start on boot. At this point, you must reboot again.

When installed, SuperNFS adds NFS Server, NFS Expert, SetupTCP, a tutorial, Help and documentation, and an Uninstall program. The UI is well organized and easy to navigate. SuperNFS presents a limited number of menus, including Databases, Server, Statistics, and Help. You use Databases to set up User Mappings and Group Mappings and to configure the exports database, which contains the list of folders that clients can access. SuperNFS lets you use password and group files imported from UNIX servers. You can also set up NIS through the Server menu's Configure option. Other Server menu options include commands to start, stop, pause, and continue the NFS server and to reload the databases. When you reload User Mappings and Group Mappings, SuperNFS performs normally and clients continue to see the NFS shares SuperNFS exports.

NFS Expert helps check the NFS network and potentially diagnose network or system problems. The NFS Expert utility is useful for reviewing remote procedure call (RPC) services available on a particular host. For example, you can request servers to respond if they have a specific RPC program, as Screen 4 shows.

NFS clients on other systems can access files and printers on the server. However, we noticed one problem when you use the SetupTCP program to configure the NFS server. When you click the SetupTCP program options, you automatically reboot the server. If you work in a production environment, this feature might be inconvenient.

Initially, SuperNFS added icons for Help and a tutorial but didn't install the corresponding files. We downloaded the documentation from Frontier Technologies' Web site and expanded the Zip file in the Program FilesFrontierTech folder. This product's Windows Help files and documentation are impressive, and you can find a set of tutorials on the support Web site (http://support.frontiertech.com). The tutorials guide you through NFS server setup, give an excellent overview of performance tuning, and provide step-by-step instructions for troubleshooting common problems and optimizing NFS server performance. The Help files also address concerns such as I/O failures, NFS response-time improvements, and printing problems. Although the screen shots are from earlier NT versions, the tutorials do a great job of teaching how to set up NFS servers.

In our tests, SuperNFS ran for more than 4 weeks without an application error, and it was manageable and easy to use. One drawback is that this product doesn't support WebNFS. However, if you're not concerned with WebNFS and want a user-friendly NFS server, you might choose SuperNFS.

Omni-NFS Server
Of the products we examined, Omni-NFS Server is one of the least expensive packages and requires the least amount of user input to install and configure. After you install the software, it runs as a service. For NFS clients, Omni-NFS Server provides standard NFS exports and shares files and printers on NT computers. Installation and configuration are straightforward, and you can easily mount shares on NFS clients.

However, the vendor didn't organize Omni-NFS Server's documentation as well as that of the other NFS servers we reviewed. The explanations are rudimentary and not particularly informative for resolving or troubleshooting problems. We also initially couldn't make WebNFS work, even though the vendor's Web site indicates Omni-NFS Server supports WebNFS. Standard commands such as Showmount and Mount worked properly, but the server didn't respond to WebNFS clients. Xlink's technical support department suggested we use drive letters in the URL, which solved the problem.

Omni-NFS Server comes with a few utilities that the other products don't have. For example, a host editor lets you verify whether the hosts are running NFS. You can also use the host editor to add a list of servers and clients that the DNS or host file can resolve and to confirm NIS authentication. As Screen 5 shows, Omni-NFS Server uses the HostEdit utility to select authorized clients.

As with DiskShare and Server for NFS, Omni-NFS Server integrates closely with Windows Explorer. You use this level of integration and the simple UI to easily add NFS shares to NT computers. For example, when you right-click a folder to share it in Windows Explorer, you'll see an NFS Sharing tab that you use to specify authorized clients and directory access rights. However, Omni-NFS Server doesn't work as smoothly as DiskShare and Server for NFS do. For example, the only way you can change the list of authorized clients is to clear and recreate it. You also can't change the status of specific clients after you add them to the list.

One of this product's major drawbacks is that it lacks troubleshooting tools. Omni-NFS Server includes a few tips about how to optimize performance and troubleshoot problems, but it doesn't have tools comparable to those that NFS Maestro Server, Server for NFS, and SuperNFS offer.

Your Choice
We didn't find significant performance differences among the six NFS servers we reviewed. All of the products performed well in terms of providing NT resources to UNIX computers. NFS Maestro Server is an easy-to-use package with excellent documentation. Some of the configuration dialog boxes are cluttered and confusing, but after you configure NFS Maestro Server, the product performs well. However, the vendor needs to fix the bug with WebNFS. We like the product's additional utilities, which you can use to troubleshoot installation and configuration problems.

InterDrive Server provides concise management and configuration options. However, you might find the product's Server Control application confusing and miss the standard Win32 applications that this product lacks.

If you like NT management and administrative interfaces, and don't care about WebNFS, look into DiskShare or Server for NFS. We like these two products' integration features that let you quickly access Share and Server options from within Windows Explorer.

You might choose SuperNFS if you're looking for an easy-to-use package and if WebNFS isn't a crucial factor. If you're new to NT or NFS, the tutorials and clear documentation are especially attractive features.

Omni-NFS Server doesn't appear to be in the same league as the other products we reviewed. Documentation is rudimentary, and the product doesn't install or function as easily as the others do.

When choosing your NFS server, you need to consider one more product feature—availability. As a result of acquisitions and product-line consolidation, fewer NFS servers for NT are available than were available a year ago. Even some of the products that are currently available might not be in the near future. Before you spend time researching the right NFS server for you, make sure it still exists.