[Dnsmasq-discuss] How to get name of DHCP'ed system?

bod at bod.org bod at bod.org
Sat Jan 24 16:26:08 GMT 2009


Simon Kelley wrote:
> Chris G wrote:
>> I have just moved fully to using dnsmasq on my xubuntu 8.10 system,
>> it's made things much simpler than they were.  I have removed all my
>> manually added entries for static IP hosts on the LAN from /etc/hosts
>> and I've "un static IP'ed" them - dnsmasq does it all for me.
>>
>> However I have one issue, I have a couple of things which are not
>> computers on the LAN, there's an HP printer and a Siemens DECT/VOIP
>> box.  I have set them to use DHCP to get their settings but I don't
>> know how to find what their names are.
>>
>> It's easy for a computer on the network, I have set the name when
>> installing the OS so I know what the name is.  But I don't know how to
>> find the name of a box whose name I'm not able to set myself.
>>
>> How can I find DNS names of systems which dnsmasq knows about?
>>
>
> It's quite possible that they don't have names, or are not sending 
> them as part of the DHCP reuests.  If there is a name, it will be 
> logged by dnsmasq at the end of the line where it logs the DHCPACK. 
> (look in syslog).
>
Isn't that the hostname that dnsmasq is sending back to the requester? 
which may not be the same as the original client ID/name that the 
requester sent? (if any). Would it be hard to have the DHCPREQUEST log 
message include the name in the request, if were provided?

I've been (half-heartedly) poking around at a similar problem to Chris's 
- I have three embedded devices that provide a name with part of the MAC 
address included (HD HomeRun, Snom M3 and Vudu boxes). Since I only have 
one of each (and have a hard time remembering long hex numbers :), I'd 
like to override the hostname sent with a shorter one.

So, one example (snipped from dnsmasq.leases)

1232816970 00:18:f9:03:0f:27 10.11.1.190 Vudu-0x3783 *

I'm guessing the trailing * means that no client id was provided. So the 
'Vudu-0x3783' was provided by the device as a hostname in the request? 
must've come from the device somehow, I didn't specify it anywhere :)

So I've tried:
  dhcp-host = Vudu-0x3783,10.11.1.81,vudu
and
  dhcp-host = id:Vudu-0x3783,10.11.1.81,vudu

with no success. Using the MAC address works, of course. Which is why I 
haven't been too worried about solving this; though I am curious...

-- Paul





More information about the Dnsmasq-discuss mailing list