Can dhcpd update DNS with netbios names?

Hello,

I have a Linux router/gateway with mostly Windows clients attached.
The router is running Samba, DHCP v3 and Bind v8; DDNS updates are
enabled. How do I get the DHCP server to update the DNS server with
the names of the Windows clients? Those names are stored in
/var/lib/dhcp3/dhcpd.leases by dhcp3, so it shouldn't be too hard for
dhcp3 to notify Bind of the computer names. How would I go about doing
that?
Thanks,

Peter

Peter Klein wrote:
> Hello,
>
> I have a Linux router/gateway with mostly Windows clients attached.
> The router is running Samba, DHCP v3 and Bind v8; DDNS updates are
> enabled. How do I get the DHCP server to update the DNS server with
> the names of the Windows clients? Those names are stored in
> /var/lib/dhcp3/dhcpd.leases by dhcp3, so it shouldn't be too hard for
> dhcp3 to notify Bind of the computer names. How would I go about doing
> that?
> Thanks,
>
> Peter
Normally this is the client systems responsibility. dhcp will assign a
name and address to a client system, and then that system needs to run a
dynamic dns client to send the ipaddress and hostname on to the dns
server. Most of the clients are run manually, or as a daemon that
watches a configured interface for address changes. I suppose it would
be fairly easy to write a script in a cron job to watch for changes to
the lease file on the dhcp server and notify the dns server on the
clients behalf, but normally the client does this itself.

HTH
Neil

--
Neil Horman
Red Hat, Inc., http://people.redhat.com/nhorman
gpg keyid: 1024D / 0x92A74FA1, http://www.keyserver.net

Never mind, dhcp does that automatically. Setting up DDNS is all that
was needed and I can now do "ping windows-client" from any computer on
the network.

Peter

Peter Klein wrote:

> Never mind, dhcp does that automatically. Setting up DDNS is all that
> was needed and I can now do "ping windows-client" from any computer on
> the network.

If your existing DDNS setup is working, this won't be important to you,
but I thought I'd post in case anybody else is interested....

Two other possible approaches to doing this, or something that might be as
good, are:

1) Set up a Samba system to handle NBNS (aka WINS) duties and use the
"wins hook" parameter in smb.conf to call a script called dns_update
that ships with Samba (at least 2.0.x and 3.0.x; it seems to be missing
from at least some 2.2.x releases). Set up the DNS server to accept
dynamic updates. The result is that the Samba NBNS system will notify
the DNS server of NetBIOS names as they're registered and un-registered
by the clients. This is a bit tedious to set up, but is at least
potentially handy.
2) On Linux systems that should be able to contact systems that have
registered NetBIOS names, edit the /etc/nsswitch.conf file and add
"wins" to the end of the "hosts:" line. This adds support for NetBIOS
name resolution to the normal Linux name resolution system (which
usually handles resolution via /etc/hosts, NIS, and DNS). This won't
help systems on the Internet at large to contact your systems, though,
or for that matter any systems you don't modify in this way. It's a
quick and easy solution if you just want a few Linux boxes to be able
to address Windows systems (or even other Linux systems, if they run
Samba) by NetBIOS name.

--
Rod Smith, (E-Mail Removed)
http://www.rodsbooks.com
Author of books on Linux, FreeBSD, and networking

Peter Klein <(E-Mail Removed)> wrote:
> Never mind, dhcp does that automatically. Setting up DDNS is all that
> was needed and I can now do "ping windows-client" from any computer on
> the network.

How do you stop clients (re-)registering names such as "www" or "wpad"
(arrggh!) within your DDNS domain?

Chris

> How do you stop clients (re-)registering names such as "www" or "wpad"
> (arrggh!) within your DDNS domain?

Tell them to name their computer something different?
If that is no option, you could have DHCP assign fixed IPs to those
ethernet addresses and assign a name of you choice to each IP in DNS.

Peter

Peter Klein <(E-Mail Removed)> wrote:
>> How do you stop clients (re-)registering names such as "www" or "wpad"
>> (arrggh!) within your DDNS domain?

> Tell them to name their computer something different?

Fair point, but I was hoping for an automated (technical) option :-)

> If that is no option, you could have DHCP assign fixed IPs to those
> ethernet addresses and assign a name of you choice to each IP in DNS.

I'm asking in the general case where I might not know that someone's
decided to play silly and rename their PC "to see what happens". I don't
want my domain falling on its ears just because someone's decided to
call their PC "mail", but I would like to consider using DDNS.

I guess one option is to put the entire DDNS range into a subdomain
(e.g. *.pc.roaima.co.uk in my case), which is quite acceptable to me,
if not so "elegant". I suppose I'd then still need to preallocate
wpad.pc.roaima.co.uk, though.

Cheers,
Chris