dhcpd related issues

James Tanis james at tanis.us
Mon Sep 21 10:45:36 UTC 2009

Yeah, it seems to be the case that enough traffic was being generated  
to delay the dhcp leases that the client computers were giving up. I  
used dhcping to watch and witnessed it in action. Moving dhcp to  
another server solved the issue. Likely I'll be moving some other  
services off that server soon to cut down on other "hotspot" related  

James Tanis
Technical Coordinator
Computer Science Department
Monsignor Donovan Catholic High School

On Sep 20, 2009, at 10:41 PM, Olivier Nicole wrote:

> Hi James,
>> I have a FreeBSD 7.0 gateway/server with isc-dhcpd 3.1.2p1_2. Late
>> yesterday I began having some unique and intermittent issues.
>> Basically, random computers will all of a sudden lose their dhcp
>> leases and be unable to contact the dhcp server.
> I did not see any reply to your question.
> It happened to me that a secondary switch was working badly with
> DHCP. If I rebooted the switch, it would work for a while, then fail
> again. But that was a sort of random failure, some ports would be
> affected sometime. The problem would occur a the first lease in the
> morning rather than at renewal time.
> As it was a cheap switch, unmanageable, I replaced it.
>> Sep 17 14:03:15 grendel dhcpd: ICMP Echo reply while lease
>> valid.
>> Sep 17 15:25:19 grendel dhcpd: ICMP Echo Reply for late
>> or spurious.
>> which doesn't seem particularly relevant or heinous. Many more
>> computers than the ones above have been affected.
> I don't remember ever seeing such error, but I would think that late
> or spurions is not that innocent: it could be the symptom of a switch
> not working at its nominal speed.
> Of  course you could  also consider  a computer  on that  switch being
> infected by some kind of virus and generating so much traffic it takes
> your switch out.
> Bests,
> Olivier

More information about the freebsd-questions mailing list