Re: dhcpd with multiple interfaces.

From: Cameron Kerr (
Date: 04/13/04

Date: 14 Apr 2004 10:34:22 +1300

Eksa <> wrote:
> Cameron Kerr <> wrote in message
> news:<>...
>> Perhaps you should show us the guts of your config file.
> Okay, here they come.
> Access points are connected to these interfaces: eth2 inet
> addr: Bcast: Mask: eth3 inet
> addr: Bcast: Mask:

Well that's just silly. The broadcast address should be different for
each subnet.

$ ipsc -a
Network address:
Full subnet mask:

Subnet 1:
Subnet 2: *
Subnet 3:
Subnet 4:

IP address:
Host allocation range: -
Full subnet mask:

So the broadcast address assigned to eth2 should be
eth3 should have

> option domain-name-servers

It is better to specify this on a per-subnet (interface) basis. Usually.

> subnet netmask {
> authoritative;
> option subnet-mask;
> option broadcast-address;

Ah, so you do have that right. Is it right on the server?

> So, here the client changes from AP1 (eth2) to AP2 (eth3). After a
> some kind of timeout the client sends DHCPDISCOVERY message and
> everything works fine. However, this break is something like one
> minute. I think that there is some kind of bug in DHCP server, since
> it really should NAK the DHCPREQUEST received via eth3, but it keeps
> ACK:ing...

I concur. But I would suggest that you try to replicate the problem
using just plain ethernet befare ruling it as a bug with DHCPd.

Cameron Kerr :
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