nmbd & netbios name -> many addreses

Pierre MONDIE pm at univ-evry.fr
Thu Mar 11 18:38:56 GMT 1999

	I'm unsure my answer belongs to the list policy : just LMK, and forgive
the poor English of a little Frenchie.

>Here is a sample from the wins.dat file:
>"KUDOS#00" 921670223 44R
>"KUDOS#03" 921670223 44R
>"KUDOS#20" 921670223 44R
>Now what is the solution:
>a) WINS clients (ie kudos in this case) only register 1 address


A given <00> NetBIOS node (workstation) or <20> node (file&print server) is
an "unique" record in any WINS server, whether the name has been
dynamically recorded or not.

>b) WINS servers only give out 1 address (perhaps using DNS like approach of 
>giving same subnet as requester if exists)

A WINS server parses its database and answer according to the first record
matching the node "name" (eg. record). If a static record exists, it's
parsed before dynamically generated records/reservations.

>The other thing I have not been ale to test is what a multihomed NT box
does - 
>we do not have any.

>Finally I am very surprised no one else has encountered this?

This is quite a common problem but may sometime be uglily solved through IP
routing. If the NetBIOS node -(workstation for example) has multiple IP,
only ONE is linked to NetBIOS and therefore tries to record itself to the
WINS dynamic database. If the workstation admin does not handles this, the
first "NetBIOS->WINS name record query" packet coming to the WINS will
-prolly receive registration agreement and the next won't because the name
is already recorded. This may lead to random behavior.

note that nmdb can be used to solve these problems from a centralized
approach, but interaction between WINS & samba nbns may lead to
unpredictable results because of differents behavior/designs.

NetBIOS name resolution and network neigbourhood are not strictly related
one to each other. Network neighb. is a pure NetBIOS service and relies on
every workstation binds between NetBIOS and "real" network protocols.

>> On Sat, 6 Mar 1999, Peter Polkinghorne wrote:
>> > > That is, that your Samba 1.9.18p10 server is acting as a WINS (NBNS)
>> > > server and as the Domain Master Browser, right?  That rev of Samba 
>> > > doesn't have the Domain Control functionality active, so I assume
>> > > using it as a DMB.
>> > >
>> > Yes - Domain Master Browser - too much of this terminology is getting
>> > keywords in the right order :-(.
>> >  
>> > > 
>> > > I don't recall any changes between 1.9.18 and 2.0 that would have fixed
>> > > this, but I often miss these things.  The big change in nmbd (from my
>> > > perspective) was that the namelists were converted from linked lists to
>> > > splay trees, for speed.  Before 1.9.18 I didn't have my hands in, so I
>> > > don't know what might have happened in between. 
>> > >
>> uh... actually... that means... ok.  it's a bit complicated to explain in
>> a short email, check against 2.0 and let the list know your findings:
>> there may be a bug here.
Pierre MONDIE : SSR : 74-78

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