DHCPDISCOVER packets being received by host, but not responded to by dhcpd

[Kyle Dion]

Hi all,
This is kind of an off the wall question, and I'm not sure if this is 
the right place to ask it.  If this is not the right forum, then I 
apologize in advance.  I am running a pair of ISC DHCP 4.0.1 servers, 
with failover, on RHEL4 (32-bit).  Generally, this setup works 
flawlessly.  However, I have run into a situation recently, where a 
small number of clients are sending DHCPDISCOVER packets to the servers, 
and I have been able to confirm with packet captures on the server, that 
the host is receiving them.  However, the logs never show that dhcpd 
received or recognized the DHCPDISCOVERs.  Also, maybe not surprisingly, 
the server-side packet captures show that the server never responds with 
a DHCPOFFER (or any other message).  The DHCPDISCOVER packets AFAICT 
with Wireshark *are* valid, so I am at a loss.  Any light that could be 
shed on this or any guidance as to further troubleshooting steps or a 
better place to escalate this would be greatly appreciated.

Thanks,

-- 
Kyle Dion
Technical Operations
VMware, Inc.
kdion at vmware.com