Thanks Herman,
That makes a lot of sense. Just what I needed to know.
Regards,
Daniel
On Fri, 2003-11-21 at 00:53, Herman Verkade wrote:
> On Thu, 2003-11-20 at 22:57, Daniel Fone wrote:
> > Hi guys,
> >
> > I have a question regarding dhcpd. And before you tell me to rtfm,
> > please specify the "fm" because I've been through a few.
> > I have a small network at home that gets IP, gateway, nameservers etc
> > from my linux box running dhcpd. I would like to specify the TCP
> > hostname using DHCP. Is this possible? What is the best way to identify
> > a client in the conf file? I have windows and linux clients.
>
> You can for the Linux clients, but not for the Windows clients.
>
> To a Linux machine, its name is a minor attribute that it does not use
> itself very much. When you configure dhcpd to send the host name to the
> clients, the Linux clients will use this as the host name. To do this
> you need to specify use-host-decl-names as "on" in your dhcpd.conf file.
> You would then need to create an entry for each machine in your
> dhcpd.conf file which specifies a unique entity for each client to map
> names to clients. The hardware ethernet address is the most commonly
> used entity for this, so you'd map ethernet addresses to names, for
> example:
>
> host pcone { hardware ethernet 00:12:34:56:78:9a; }
> host pctwo { hardware ethernet 08:00:fb:9a:39:10; }
>
> When dhcpd receives a request from the 00:12:etc hardware address, it
> will send a reply with "pcone" as the hostname option, and Linux clients
> will use this value as their hostname.
>
> An interesting additional option of the ISC DHCP implementation is that
> you can use an 'expression' in the dhcpd.conf file to mangle the
> ethernet address into a unique hostname (such as pc00123456789a), in
> which case you no longer need to have an entry for each machine on your
> network, but you do end up with crappy machine names.
>
>
> On Windows, everything is different... Windows Networking uses the
> NetBIOS protocol, which can run over a number of different protocols, of
> which TCP/IP is just one (albeit the most commonly used one). On a
> Windows PC you specify a NetBIOS name which the machine uses as its main
> machine name. You can separately specify a host name in the TCP/IP
> settings, but this needs not be the same as the NetBIOS name and is
> largely ignored by Windows. Both names are configured locally on the
> client and stored in the Registry and the DHCP option for the hostname
> is completely ignored by Windows. In fact, when you look through the
> dhcpd.leases file, you will see that the client already sends its name
> in the DHCP request, at which point it is too late to overwrite it.
>
> HTH,
> Herman
