client refuses to accept offer

[Richard Pijnenburg]

-----Original Message-----
From: dhcp-users-bounces+richard=softwaredev.nl at lists.isc.org
[mailto:dhcp-users-bounces+richard=softwaredev.nl at lists.isc.org] On Behalf
Of anctop
Sent: donderdag 13 mei 2010 2:26
To: Users of ISC DHCP
Subject: Re: client refuses to accept offer

To Chuck Anderson :

> Usually the routers and subnet-mask options go in the subnet block
> rather than the host blocks because they are more related to the
> properties of the entire subnet and would be the same for all hosts in
> that subnet.  They should work in the host blocks in any case--it is
> just a bit unusual to configure them there.
>
> I notice that your router is not in the same subnet as the client.
> That is probably a misconfiguration.  The router should probably be
> 147.8.108.1 or similar.  Maybe this is why your clients are rejecting
> the offers.

The router setting does look unusual, but this is what the local net.
admin has told me for configuring static IP addresses.

To Simon Hobson :

> I'm confused ! You say there is no traffic to/from the DHCP server,
> but then say it's from 0.0.0.0 to 255.255.255.255.
>
> The initial DHCP-Discover will be from 0.0.0.0 as the client doesn't
> have an IP address at this time. It's always to 255.255.255.255 (the
> broadcast address) as it doesn't know the address if the server.
> The server will respond to the broadcast address as well.

By "no traffic to/from the DHCP server", I mean none of the wireshark
DHCP entries has the address of my server as source or destination.

I think Randall C Grimshaw may have told the most likely cause.

> Sounds like the network is suppressing your DHCP, possibly using Cisco
> DHCP-snooping or similar. This would not be surprising in an enterprise
environment
> where DHCP can be very disruptive. Its use should always be coordinated
through
> your central administration.

I'll try to justify it.

Regards,
anctop


Actop:

I'm not sure how your network is setup but would like to share this:

if you have a cisco router with different routed interfaces you'll need to
setup a helper-ip on those interfaces telling where it can find the DHCP
server.
This will forward all requests to the dhcp server.

Regards,

Richard