[afnog] Windows IP Conflict

[Brian Candler]

On Mon, Dec 19, 2005 at 07:24:42AM +0000, Maggie Yamfwa wrote:
>    Can anyone help me.  I am running a windows 2000 DHCP server.  I have
>    excluded a range of IP address which I have manually  assigned to
>    servers and the rest are automatically assigned.  But some computers
>    on the network are still picking the IP addresses from the excluded
>    range and giving a conflict.  It also happened when I used the
>    reservation.  There is also an access point on the LAN which is
>    connected to ethernet switch.

On the clients, try using an ethernet sniffing tool to look at the DHCP
OFFER packets they receive, to see (a) which DHCP server is handing out the
addresses, and (b) what address is being handed out. Then you can find out
whether your Win2K DHCP server is misbehaving/misconfigured, or whether you
have some other DHCP server on your network that you're not aware of.

This should also work if you plug your sniffer into a hub (but not a
switch).

Also, if your Win2K DHCP server has a request logging facility, try turning
that on to see what is happening.

Regards,

Brian.