Home network issues

[mikeybrass]

Hi,

I hope someone may be able to help me. It is a networking issue unrelated to both the Mac and Windows laptops we have.

We are with NTL and have their 250 cable modem.

Original configuration: cable modem connected to a Belkin router. The router obtained its DHCP lease fine, it dished out internal DHCP fine to the two laptops. No problems there.

Connected a Linksys WRT54G wireless to the Belkin router. The wireless is configured for "auto configuration - DHCP", to pick up its DHCP from whatever it happens to be connected to. No problem there either.

What happened: because the Linksys is also a wireless router, I wanted to connect it up solely to the NTL modem. Plugged the modem in directly but, while I could pick up a DHCP lease on my comp with the wireless, there was no internet connection.

I changed the setup back to the way it was originally (wireless plugged into the router, modem plugged into router) and rebooted the three devices. No change - no internet connection.
So what I did was hook either laptop up to the modem directly. I shut both the laptop and the modem off, turned the modem back on and then the laptop. Bingo, Net connection.

So then I connected the modem up directly to the wireless again, connected my laptop by ethernet to the wireless and looked at the configuration of the wireless. Spotted the problem - although the wireless is set to get its DHCP from the modem ("auto configuration - DHCP"), it was not. No DHCP lease, no default gateway assigned.

However, if the wireless is connected to the router, the wireless is assigned a DHCP lease with a default gateway (the address of the router). But then the router in turn is not picking up a DHCP and gateway from the NTL modem.
But then if either laptop is connected directly to the NTL modem, the laptop gets assigned a DHCP and gateway, getting on to the internet.

Help, any ideas??? I have restarted the wireless, router and modem countless times. Help???




---------- Post added at 11:32 ---------- Previous post was at 10:43 ----------

Hmmm....maybe this is the reason (I'm at work now and cannot test out my idea).
No Mac address is registered in the Device Admin on the wireless. As this would not supply a Mac address to the NTL modem, would I be correct in saying this is why the cable modem does not return DHCP, gateway, DNS settings to the wireless?

[Paul K]

Are you plugging a wireless router into your wired router for a reason? The easiest way would be to remove the belkin and then get the modem to talk to the WRT54G directly. Currently the modem only remembers the belkin set up so you could either clone the info onto the WRT54G or get the modem to behave with the WRT54G itself.
Have you tried powering all off, leave for a couple of mins, power up modem, leave to settle, power up WRT54G, leave to settle, power up pcs.

[mikeybrass]

Originally Posted by Paul

The easiest way would be to remove the belkin and then get the modem to talk to the WRT54G directly.

I did that.

I first connected the wireless router into the Belkin router because my fiancee was online at the time chatting and it would have been a disruption. So when she was done, I tried connecting the NTL modem directly to the wireless.

Currently the modem only remembers the belkin set up so you could either clone the info onto the WRT54G or get the modem to behave with the WRT54G itself.

I am at work but realised that what is missing is my computer's Mac address cloned into the wireless router. As I understand it, NTL requires that in order to assign DHCP, DNS and gateway to the router. I'll be doing that this evening.

[Aragorn]

The cable modem doesn't need to register all MAC addresses, only STB's worry about pre-registered MAC's.

When you get home, power off everything, plug an rj45 cable from the CM to the 'internet' port on the Linksys, and another cable into you laptop from port 1.

Power on the CM and let the light settle. Then power on the Linksys and finally the laptop.

Browse to the UI of the router (192.168.1.1 - default pwd admin) and see whether it has a valid IP assigned by NTL. If not, browse to 192.168.100.1 (CM interface - root/root) and see whether that has an IP address.
Also let us know what LED's are on the Linksys and CM.

HTH

[mikeybrass]

Originally Posted by Aragorn

The cable modem doesn't need to register all MAC addresses, only STB's worry about pre-registered MAC's.

When you get home, power off everything, plug an rj45 cable from the CM to the 'internet' port on the Linksys, and another cable into you laptop from port 1.

Power on the CM and let the light settle. Then power on the Linksys and finally the laptop.

Browse to the UI of the router (192.168.1.1 - default pwd admin) and see whether it has a valid IP assigned by NTL. If not, browse to 192.168.100.1 (CM interface - root/root) and see whether that has an IP address.
Also let us know what LED's are on the Linksys and CM.

HTH

Already done all the above - see my original post where it says that the router was not assigned an ip address, gateway or DNS by NTL, but that the NTL modem is fine. Only thing different between a setup which worked and one which has a problem is a Mac address entry.

Going to try that tonight - it was a solution which worked for someone else having the same problem as me on another computer board. Will let you know how I get on.

[crazybones]

Mikeybrass,

Your problem sounds strangely similar to mine that I posted here:

http://www.cableforum.co.uk/board/sh...3&goto=newpost

I thought that the Linksys router had a problem, but have since found that it's actually the cable between the cable modem and the router. If my pc is connected directly to the NTL 250 using the same cable, I can gain an IP address and access the internet. If I then put the Linksys router on the same cable, I can't get an IP address.

Now here's the strange part, if I substitute a spare 2m CAT5 cable, the Linksys router works fine, so I know that its a cable issue in my case. Either the cable (10M) is too long and the losses are too great or there's a compatibility problem. My existing cable was not CAT5, so the next thing that I'm going to try is substituting a 10M CAT5 cable and if that doesn't work, I'll buy a shielded CAT5 cable.

Hope this helps.

[mikeybrass]

Thanks for the help, CB. I've got a dozen cables of variable lengths at home and had tried more than one over the course of two hours (over last night and very early this morning) prior to going to work and posting.

It turned out to be the Mac address. I connected directly to the Linksys with an ethernet cable, cloned my computer's Mac address, shut down everything, brought first the NTL modem, Linksys and finally my laptop up (I had tried this sequence before, without enabling the Mac address function on the Linksys). Success. Both my comp and my fiancee's are now connected via wireless. Am pleased:-)

I hope this post finds its way into google and helps someone else in the future.

[Druchii]

Originally Posted by mikeybrass

Thanks for the help, CB. I've got a dozen cables of variable lengths at home and had tried more than one over the course of two hours (over last night and very early this morning) prior to going to work and posting. It turned out to be the Mac address. I connected directly to the Linksys with an ethernet cable, cloned my computer's Mac address, shut down everything, brought first the NTL modem, Linksys and finally my laptop up (I had tried this sequence before, without enabling the Mac address function on the Linksys). Success. Both my comp and my fiancee's are now connected via wireless. Am pleased:-) I hope this post finds its way into google and helps someone else in the future.

Itll get there alright, the googlebot loves forums...

[crazybones]

Glad to hear that your sorted mikeybrass. I tried cloning the MAC address but it did not help. I must admit that as Aragorn said above, I understood that cable modems did not need pre-registered MAC addresses - only STB's. That said, at least you're up and running and that's the main thing.

I'm off to play with my cables!