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Christopher R. Hertel
crh at nts.umn.edu
Mon Jan 1 20:00:34 GMT 2001
Alex Vandenham raised a question that I find interesting. Here, if I
have it right, is the scenario:
Lan1
|----------+---------------+--|
| |
[LMB: FOO] [Router]
Lan2 |
|------+-----------+-------+--|
| |
[LMB: FOO] [LMB: URQ]
That is, Lan1 has a workgroup named FOO. Lan2 also has a workgroup named
FOO as well as a workgroup named URQ.
Now add a Domain Master Browser and a WINS server to the above. They can
go anywhere. It doesn't matter where they reside. The DMB is for
ntdomain FOO, thus promoting both FOO workgroups to the status of a
single ntdomain.
Lan1
|----------+---------------+--| [DMB:FOO]
| | |
[LMB:FOO] [Router]---+------+--|
Lan2 | |
|------+-----------+-------+--| [WINS]
| |
[LMB:FOO] [LMB:URQ]
Here's what happens:
On Lan2, LMB:FOO knows about workgroup URQ, and lists the existance of
workgroup URQ in its browse list. It eventually forwards that list to
DMB:FOO. DMB:FOO, in turn, eventually forwards the combinded list to the
*other* LMB:FOO on Lan1.
So, Lan1's LMB:FOO now knows about workgroup URQ.
Unfortunately, since WINS does not register #1D names, there is no way
for a client on Lan1 to *find* LMB:URQ, even though it knows about LMB:URQ.
Indeed, the Get Backup List Request for a workgroup is sent to the
broadcast address on the apparent assumption that only the local
<workgroup>#1D system will respond.
If a client on Lan1 could find LMB:URQ, it could send a unicast message to
get the backup list, but that's simply not how it works. My guess is that
the idea of combining workgroups and ntdomains was not considered a good
one when this was all being designed.
I would love to see some traces of this stuff. I'm curious to know if the
client on Lan1 would try sending the query on to a DMB if it could not
find the LMB for the missing workgroup. My guess is that no DMB is ever
consulted.
I hope, Alex, that I have done a good job of describing the problem. Let
me know if I'm close.
Chris -)-----
--
Christopher R. Hertel -)----- University of Minnesota
crh at nts.umn.edu Networking and Telecommunications Services
Ideals are like stars; you will not succeed in touching them
with your hands...you choose them as your guides, and following
them you will reach your destiny. --Carl Schultz
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