DHCP and Windows 2000 problem using NTL Cable Modem

[Andrew Bonello]

Hello All

I have a Windows 2000 PC with two PCI NICs installed. One connects directly
via Ethernet to a Motorola Surfboard 4200 Cable Modem, which connects to NTL
in the UK as its ISP. The NIC connecting to this card is set to act as a
DHCP client (ie. to "obtain its IP address dynamically" (from the cable
modem), which acts as a DHCP server). The second NIC in the machine has a
static IP address, and connects via a network hub to several other machines
on my LAN, all of which are assigned their own static IP addresses.

Everything works fine. At first. The machine is booted, and upon starting
IE5, my Win2k machine "detects proxy settings" from the cable modem, gets
assigned a dynamic IP, and internet access is granted.

However, after a short while, the internet access halts. It can take
anything from a few seconds to a couple of minutes for this to happen. But
it always happens. Any downloads/web access in progress simply halt, and
eventually IE5 times out and posts its DNS error page.

I have checked everything I can think of. The NTL service seems fine, the
cable modem is all patched in, no problem. (I've had numerous visits from
technicians to verify this!) I suspect the problem is to do with the
configuration of DHCP and my NICs on the Windows 2000 machine.

Has anyone seen anything like this before? What am I doing wrong? I see no
reason for the internet connection to hang in this way. Removing the second
(static IP) NIC and uninstalling its network drivers seems to make no
difference at all to this behaviour.

My DHCP-enabled NIC is set to run at 10BaseT, half-duplex, as I have read
that full duplex mode sometimes confuses this particular Motorola cable
modem model.

Could this be something to do with DHCP server and client being run on the
same machine? (As far as I know DHCP server should not be running). Could
there be a subnet conflict between the two NICs?

Any help would be much appreciated, as I have run out of ideas, and NTL's
technical support line are "unable to assist" :o(

Thanks!

Andy Bonello

[val harrop]

Getting an IP via DHCP from the modem and having your computer detect proxy
settings when you start up IE are not the same.

Your card would be get its DHCP lease from the modem when you boot up the
machine (assuming the modem is on). Run ipcfg or winipcfg (whichever is
right for your OS) to check the results for your card. It should have
obtained its lease.

Then, check you internet connection settings in your internet options, and
set it to never dial a connection, and then check under lan settings to see
if you have some kind of proxy setting in there. If so, be sure that it is
correct per NTL, or try connecting directly to the internet bypassing the
proxy server.

Here are some good websites for further resources:
www.practicallynetworked.com
www.sohointer.net
www.wown.com

Good luck,
Val