[Samba] Re: Understanding the role of DMB/LMB on a net that has a WINS server

[John H Terpstra]

On Thu, 9 Oct 2003, David Wuertele wrote:

> John, thank you for your detailed answers.  The roles of DMB/LMB are
> much more clear to me now.  I also want to mention that the Samba
> documentation is excellent, and I learned very much from the
> NetworkBrowsing.html page.  Kudos to you for doing a great
> documentation job!
>
> I have two more questions.  The first:
>
> Me> I was not able to discover whether nmbd is *required* to be
> Me> running on a workstation that doesn't publish any shares, and just
> Me> uses smbclient or smbmount to access other servers' shares.
>
> John> Yes, nmbd is required - it provides the name resolution services
> John> for smbd.
>
> But I don't have to run smbd in order to be a client, do I?  In fact,
> I know I don't, because I can run "smbclient //SOMESVR/SOMESHARE" from
> my linux box, without that box running smbd or nmbd, and somehow the
> share name and server name gets resolved.
>
> So it seems to me that nmbd is *not* required to be running on a
> workstation that doesn't publish any shares.  If that workstation will
> never be used to publish shares or serve as a master browser, is there
> any down-side to not installing nmbd?

You do not need nmbd for smbclient, only for smbd. smbclient will use the
"name resolve order" in your smb.conf file.

> Question two:
>
> Are all types of netbios name that are listed in the table in
> http://ubiqx.org/cifs/Appendix-C.html resolved by a WINS server?  For
> example, I have a windows box that responds to nmblookup like this:
>
> # nmblookup -A 192.168.0.111
> Looking up status of 192.168.0.111
> 	ABCDMEDIA       <00> -         M <ACTIVE>
> 	NOGROUP         <00> - <GROUP> M <ACTIVE>
> 	ABCDMEDIA       <03> -         M <ACTIVE>
> 	ABCDMEDIA       <20> -         M <ACTIVE>
> 	NOGROUP         <1e> - <GROUP> M <ACTIVE>
> 	NOGROUP         <1d> -         M <ACTIVE>
> 	..__MSBROWSE__. <01> - <GROUP> M <ACTIVE>
>
> Would a WINS server store a record for each of the lines in this
> response?  I saw mention that a WINS server only has to respond with
> up to 25 name resolutions per request.  If a client makes a request
> for "ABCMEDIA", and if there happens to be more than 25 different
> records of various ABCMEDIA services, will some of those records not
> get returned?

The limit of 24 or 25 addresses applies only to group names. Unique names
will never have more than a few key registrations (typically fewer than
5). In your example ABCMEDIA looks like a server. Servers will register
the type <03>, <00>, and <20> names. They may register a few other
specially configured names but that is rare.

Remember: WINS does not know anything about shares!

> Thanks again for the excellent docs,

:)


- John T.
-- 
John H Terpstra
Email: jht at samba.org