Computer Shows up as "unknown" in Router

Derek Broughton news at
Sun Oct 30 20:23:28 UTC 2005

Carthik Sharma wrote:

> On 10/29/05, Robbo <ml at> wrote:
>> On Sat, 2005-10-29 at 13:19 -0400, Carthik Sharma wrote:
>> > Hi,
>> >
>> > I have a D-link router, and have three ubuntu boxes at home. When I
>> > got the router management page and look at the DHCP clients that are
>> > connected to the router, I see either "unknown" or " " as the name for
>> > the ubuntu boxes. Managing these becomes a pain, as i have to resort
>> > to finding out the MAC address to do this.
>> >
>> > The Winxp boxes have their designated names.
>> >
>> > The hostname for the ubuntu boxes are et, and they are not set to
>> > "unknown" or " "
>> >
>> > Can someone help me name my ubuntu machines so that the router will
>> > know them by name? Thank you.
>> > Carthik.
>> Have a look at the config file /etc/dhcp3/dhclient.conf for the option
>> send host-name.  For example...
>> send host-name ""
> I changed it to
> send host-name "umberto"
> and it works!!
> Thanks
> Note: Shouldn't things be so that the name in /etc/hostname
> automatically gets sent when a DHCP request is sent? Is something
> broken, worse, is this a BUG?

No.  That might not be bad as a default, but it's entirely possible that you
might have 5 network interfaces all answering to a different name (not
likely on a home machine but common on servers).  [I've been meaning to
check for the last couple of weeks if my main DHCP server is capable of
recognizing more than one hostname in "send host-name" - it puts me into
its DNS, and I'd like to get an alias, too.  Probably won't work, but...
Anyway, I digress.]

The "correct" place for this hostname should be in /etc/network/interfaces,
where "some" DHCP clients supposedly get the value to send from the
"hostname" parameter.  However, man interfaces specifically says that some
clients don't recognize this - and dhclient3 is definitely one of them.

More information about the ubuntu-users mailing list