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Hour 13
NetWare Networking Basics
I met a traveler from an antique land
Who said: "Two vast and trunkless legs of stone
Stand in the desert. Near them, on the sand,
Half sunk, a shattered visage lies, whose frown,
And wrinkled lip, and sneer of cold command,
Tell that its sculptor well those passions read
Which yet survive, stamped on these lifeless things,
The hand that mocked them and the heart that fed.
And on the pedestal these words appear-
"My name is Ozymandias, king of kings:
Look on my works, ye Mighty, and despair!"
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and level sands stretch far away.
-Percy Bysshe Shelley
Novell could be compared to the Roman empire; it owned the entire
networking map at one time and was considered the only game in town
for serious file and print networking. In recent years, however,
Novell has lost some significant market and mind share to Microsoft's
NT. Has the time come for Rome's fall? Probably not. Novell's products
have bounced back considerably from their state of decay five years
ago, and they have the only mature directory service shipping today-a
really big deal to network geeks. The speed and reliability of Novell
servers still make them a compelling choice. Also, because Novell
servers run in a nonwindowed environment, they take far fewer
resources to run than Windows NT, because they can concentrate on file
and print services, not windowing.
Still, a lot of shops out there are ripping out their old Novell 3.x
servers and putting in NT servers. This is more or less a holy war
among geeks: As with the Token-Ring/Ethernet battle, you have your NT
zealots and your NetWare zealots. Who's right? Look, they're all
crazy.
Nonetheless, I'm going to take a firm stand here: NetWare is good for
some things, and NT is good for others. Seriously, there are certain
client/server applications that just won't run on a Novell server.
However, Novell does offer really fast file and print services, and it
has one thing that no other viable commercial network operating system
offers: a really good directory service.
NDS Networking
If you have NetWare in your shop and it was a recent purchase, chances
are that it was bought because NetWare is where the Novell Directory
Service (NDS) lives. Specifically, NDS is a way to have all your
server, user, login, security, and configuration information on a
distributed, partitioned, hierarchical database, which really makes
for one-stop shopping when you're configuring the network.
Whoa! What's this distributed, partitioned, hierarchical stuff? This
sounds like a marketing phrase. Well, it is, but it's also pretty cool
stuff. In a nutshell, NDS allows you to manage more users and servers
with fewer people-which is pretty attractive to management.
NDS is hierarchical because it has multiple levels on which
information can be stored. This keeps each level uncluttered, and
makes things simple for you. Naturally, simplicity makes
troubleshooting easier.
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Old versions of DOS didn't let you create folders; all your files
used to be just sort of plopped in one location on a disk. Can you
imagine if you could only save your Office documents to one place?
Doesn't that seem crazy? This probably gives you a sense of how
important a hierarchy is to a network directory.
The downside to a hierarchical directory is that user names now
have multiple parts to them. They still have a name (referred to as
the common name), but there's also an identifier for where this
user fits into the hierarchical tree.
For example, Quizro.finance.ny.frob refers to the user Quizro, who
works in the Finance department of the New York office of Frobozz
Magical Gadgets, Inc. You can think of this as an Internet address
without the @ sign; it's just taken for granted that the first
portion is the user's name.
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The NDS is distributed because several copies of the database live on
multiple servers, making it impossible to lose the entire database if
one server goes down. Very neat!
Finally, the NDS is partitioned because different levels of the
hierarchy can be treated separately. This means the database can have
several different segments, not all of which need to be updated all
the time. Partitioning your NDS database allows you to cut down on
network traffic; if you have 10,000 users, of which only 1,000 at a
time are geographically close to each other, why would you want to
exchange the entire 10,000-user database when you update it?
Even more importantly, partitioning lets you have a large, connected
database without hogging up your wide area traffic. Let's say you run
an importing company with offices in New York and Savannah. You have a
leased line between these offices that connects the office networks
together. Because you pay for the amount of time used or data sent,
you're interested in using the line as little as possible. You're also
interested in keeping the pipeline clear so that people who are trying
to communicate between the offices do so as quickly as possible.
You would want to create a partition between the Savannah site and the
New York site, because this tells NDS that the Savannah and New York
databases should be treated as separate "distribution" entities.
Because they're not joined at the hip, the frequent replication
traffic that occurs between the distributed NDS servers will not clog
up the pipe between New York and Savannah.
Of course, this makes the NDS attractive, but power comes at a price.
Novell servers do not run using the same Windows desktop metaphor that
you've come to know and love. Instead, they run using a text-based
console, similar to what you used to see under DOS. Don't knock it,
though. Again, Novell servers aren't busy fiddling with graphics and
windows and the overhead that goes with those things. This lack of
complexity and overhead makes for a reasonably easy-to-troubleshoot
server that runs faster on less hardware.
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