[Techtalk] dhcp client doesn't see DHCPACK

[Conor Daly]

Small RH72 based network.  dhcp server serving ip range 192.168.50.10 -
192.168.50.100 via eth0.  Clients using rh72's standard dhcp method
(whatever that is!).  All machines using rtl8139 10/100 NICs.  All
connected to a 16 port unmanaged switch with a selection of bought and
handmade cables.  up to a week or so ago, the clients were happily getting
their IPs from the server but suddenly this has stopped happening.  The
server's logs show DHCPREQUEST incoming and DHCPACK outgoing but nothing
more is happening.  This suggests to me that the clients are not receiving
the DHCPACK and don't  know what to do next.  They eventually time out and
give "failed" for eth0 and continue booting but cannot operate without a
network.  I'm not sure that they are not receiving the DHCPACK since they
don't go on to a DHCPDISCOVER if they don't hear from the server they last
heard from but I can't say for sure if that's expected behaviour.  These
machines are about 2000 miles away so I can't hop over and check myself!
I have logs for the server and I can't see anything odd in there.  No logs
for the clients at present.

Any thoughts, suggestions on how to troubleshoot this one?  I'm going to
have the admin reduce to server, 1 client and the switch and see if that
helps.

Thanks,

Conor
-- 
Conor Daly <conor.daly at oceanfree.net>

Domestic Sysadmin :-)
---------------------
Faenor.cod.ie
 10:20am  up 10 days, 12:48,  0 users,  load average: 0.05, 0.03, 0.00
Hobbiton.cod.ie
 10:19am  up 10 days, 12:47,  1 user,  load average: 0.15, 0.10, 0.03