dhclient - no DHCPOFFERS received.

[lewiz]

Hi,

Just recently I've found my laptop has been taking a while to obtain a
lease. I turned on all logging to the console and found the following
(modified a bit):

dhclient: DHCPREQUEST on ep0 to 255.255.255.255.0 port 67
dhclient: Trying media "media 10base2/BNC" 1
dhclient: DHCPDISCOVER on ep0 to 255.255.255.255 port 67 interval 6

At this point a series of ``Trying media...'' and ``DHCPDISCOVERER''
are repeated (only the interval changed - 6, 12, 14, 18 then 6).

dhclient: No DHCPOFFERS received..
dhclient: Trying recorder lease 192.168.0.10

It looks to me like the DHCP server is not responding. Is this the
case? I've verified that the DHCP server is working (another machine
has no problems obtaining a lease). Any ideas?

-lewiz.

[Robin Damm]

Post by lewiz
Hi,
Just recently I've found my laptop has been taking a while to obtain a
lease. I turned on all logging to the console and found the following
dhclient: DHCPREQUEST on ep0 to 255.255.255.255.0 port 67
dhclient: Trying media "media 10base2/BNC" 1
dhclient: DHCPDISCOVER on ep0 to 255.255.255.255 port 67 interval 6
At this point a series of ``Trying media...'' and ``DHCPDISCOVERER''
are repeated (only the interval changed - 6, 12, 14, 18 then 6).
dhclient: No DHCPOFFERS received..
dhclient: Trying recorder lease 192.168.0.10
It looks to me like the DHCP server is not responding. Is this the
case? I've verified that the DHCP server is working (another machine
has no problems obtaining a lease). Any ideas?

I'm assuming the client eventually obtains a lease.

Does the problem persist if you manually release/renew the IP?

# dhclient -r
# dhclient ep0

A cache problem perhaps?

[lewiz]

Post by Robin Damm
I'm assuming the client eventually obtains a lease.

Actually, this was the odd thing. It didn't obtain a new lease at
bootup -- it actually used a cached lease (ie, couldn't contact the DHCP
server but fell back to what it usually used).

Post by Robin Damm
Does the problem persist if you manually release/renew the IP?
# dhclient -r
# dhclient ep0
A cache problem perhaps?

If I did this after it used the cached lease it actually started talking
to the DHCP server, so, yes, you were correct here.

I've actually solved the problem now. I can't understand quite what
I'd done wrong (because it was working earlier). For some reason I
hadn't changed the default media for the if from 10baseT/UTP to
10base2/BNC -- although it should have done so in the startup scripts.
Instead, I've now got /sbin/ifconfig ep0 media 10base2/BNC in
/etc/dhclient-enter-hooks, which gets executed _before_ dhclient starts
searching. It all works fine now.

Sorry for bothering everybody, it might have been a mistake on my
part.

-lewiz.