Making NT and NetWare Get Along
So, you want to add the Windows NT operating system to your network, but you
already have a lot invested in your NetWare servers. Fear not. Windows NT's
assortment of utilities and services make working with both systems painless and
productive. With information about these tools and some common problems and
solutions, you can decide what solutions are best. You'll also find out how to
implement these solutions and avoid pitfalls.
NWLink
NetWare connectivity begins
with NWLink, the low-level protocol that provides a transport for upper-level
services. NetWare uses the Internet Packet eXchange (IPX)/Sequenced Packet
eXchange (SPX) protocols, and NWLink is NT's version of them.
Although NWLink does not provide any NetWare connectivity, NWLink is
essential to the coexistence of NT and NetWare. Without NWLink, you can't
connect to NetWare servers. However, NWLink can be the source of many
difficulties if you don't configure it correctly.
All the utilities and services that the following questions address require
NWLink. Because NWLink is the foundation of all NetWare connectivity, it is the
first logical place to look when problems arise.
Q: When I installed
NWLink on my NT system, the configuration dialog asked me to specify a frame
type. What is a frame type?
A frame type is the format
of the packet that your OS will use to communicate over your network. Figure 1
lists all the available frame types. Most difficulties with frame types occur on
Ethernet networks. With Ethernet, you have four choices of frame types: Ethernet
802.2, Ethernet 802.3, Ethernet II, and Ethernet SNAP. The first two are the
most common on a NetWare network. NetWare servers before version 3.12 default to
Ethernet 802.3. The newer versions default to Ethernet 802.2. Ethernet II and
Ethernet SNAP are usually only for TCP/IP and AppleTalk, respectively. Most
other topologies have only one or two frame types. This limitation leaves little
room for error, because each topology follows its standard. Also, because
industry standards exist for frame types on most topologies, you usually do not
have a problem with frame types on topologies other than Ethernet. Since Novell
changed the frame type NetWare servers use by default on Ethernet, configuring
NWLink incorrectly is easy.
Q: How do I know which
frame type to use?
The frame type you already
use on your network is the simple answer. The most common dilemma is Ethernet
802.2 vs. Ethernet 802.3. This situation gets back to the previous answer. Find
out what you already use and stick with it. If you don't currently have a frame
type configured, use Ethernet 802.2. The difficulties start when you use both
frame types, but more on that later.
Q: When do I need Auto Detect
Frame Type, and when do I manually specify one?
The answer to this
question is easy, once you know how the autodetect process works. NT tries each
frame type until it finds one that works. First, NT tries the frame types in the
order listed in the frame type selection box. For example, with Ethernet, NT
tries Ethernet 802.2, Ethernet 802.3, Ethernet II, and then Ethernet SNAP.
NT stops when it finds a frame type, which means that NT will use only one
frame type if you set NT to Auto Detect. If no frame type responds, NT will use
the first frame type in the list. In the Ethernet example, if NT can't get a
response on any frame types, it will use Ethernet 802.2. You can deduce that you
have to specify the frame type manually if you have a frame type on your network
that is higher on the list than the frame type you want to use (e.g., you have
Ethernet 802.2 on your network but you want to use Ethernet 802.3); you want NT
to use multiple frame types (server only); or you know that NT will not be able
to detect the frame type on the network, and you want to use a type that is not
the first on the list.
Q: Can you tell me what
an IPX network number is?
This number is what
routers use to determine whether to route a packet to another physical or
logical network. Every network a router separates must have a unique IPX network
number. If multiple frame types are running on the same physical network, each
frame type will be on its own logical network and must therefore have a unique
IPX network number.
You set the IPX number on the NetWare servers and on routers. Except for
File and Print Services for NetWare and Multi-Protocol Router (MPR), you can't
set this number in NT. NWLink will always try to autodetect this number.
If NWLink can't detect an IPX network number, the default is zero.
You can route among frame types on the same physical network. However, this
routing creates a tremendous amount of network traffic, so we don't recommend
it.
Q: What is an internal
IPX network number?
The internal IPX number is
similar to the IPX network number but refers to a virtual network inside the
machine. You can think of the internal IPX network as one that the NetWare
server routes to. NetWare servers must always have an internal IPX network
number that must be unique to the entire network. You can set this number in NT,
but File and Print Services for NetWare and Multi-Protocol Router are the only
services from Microsoft that use it.
Q: How do I tell what
frame type and network number my NT system is using?
The IPXROUTE command is
your best option. If you do much work with NWLink, this utility will be a good
friend. The simplest use is IPXROUTE CONFIG, which will return a description of
all the network cards in your system, the frame type(s) they use, and the
network number. This command is indispensable when you're troubleshooting an
NWLink problem.
Client Services for NetWare
Client
Services for NetWare (CSNW) is the most straightforward of the NetWare services
NT offers and is quite useful. It runs as a service on an NT Workstation and
lets users on this system access file and print resources on a NetWare server.
As the name implies, CSNW is strictly a client. It is easy to install and use.
As with all the services we cover here, CSNW uses NWLink to communicate on
the network. So, after making sure that NWLink is installed and running
properly, add CSNW through Control Panel - Network - Add Software. The next time
you log on, NT will ask you for a preferred server. You set this value on a
per-user basis, and <none> is a valid option. If installation does not go
quite as smoothly as you want, we hope the answers to some common questions will
help.