NTL, bittorrent & mac addresses?

andy.j · 16-12-2006, 15:17

Hi guys,

First, apologies if this kind of problem has been posted and solved elsewhere, i had a quick look but couldn't find anything like my problem...

So, for about 2 weeks now i've been using bittorrent to download and share some live bootlegs (yes, legal files) and i've used maybe 30GB downstream/15GB upstream in that 2 weeks. (this is with the 4mb package.) I'm in the staffordshire WS14 area. Operating system is windows XP SP2.

A couple of days back, suddenly something happened and i couldn't access anything (web, games, messenger etc), yet the lights on the modem (a blue ntl 250 i think it is called) seemed to suggest everything was OK. I have a netgear router connected to the modem, and I could get into the router settings fine, but not the modem via 192.168.100.1, as I usually would, as it wouldn't respond. After rebooting everything I eventually found the router wasn't being "sent any info" by the modem...like not being able to get the modem's IP address etc. The modem was connected to NTL fine as far as I know - it wasn't receiving or sending any traffic though - yet it was "rejecting" the router access (i think.)

I connected the computer to the modem directly, instead of through the router, and suddenly everything worked. So I thought, the computer's MAC address is different, so if i change the router MAC address it might work - and it did, I connected everything up as before but with the router's new MAC address changed to the computer's MAC address and it worked perfectly.

But what could have caused the modem to not accept the router's old MAC address? I'm worried it was because of the bittorrent traffic, and I haven't turned it on since managing to reconnect, but I don't see why it should be that as everything I was using it for was legal and as far as I know there aren't any DL/UL limits?

Sorry this is quite a long post but I wanted to make sure everything that happened was written down. Hopefully someone can figure out what happened, I don't want it to reoccur, haha..

Thanks!

AbyssUnderground · 16-12-2006, 15:55

Bittorrent will not have caused the problem and there are no download or upload limits. Im not sure what will have caused the problem though.

jellybaby · 16-12-2006, 16:26

Is it a Belkin Router ? A friend of mine had a similar problem, and when she cloned the mac off the computer, all was ok.

andy.j · 16-12-2006, 20:46

It's a Netgear RP614.

Uncle Peter · 16-12-2006, 23:40

Are you saying that the router hadn't picked up a DHCP address from NTL? was it defaulting to an auto configuration address in the WAN status page?

andy.j · 17-12-2006, 10:16

The modem was picking up a DHCP address from NTL (as I confirmed by connecting the computer to the modem directly and the 'net then working), but the router's connection status page looked like this:

IP Address 0.0.0.0
Subnet Mask None
Default Gateway None
DHCP Server None
DNS Server None
Lease Obtained None
Lease Expires None

I clicked renew to try and get it to connect, but it wouldn't have any of it until I changed the MAC address of the router. Then, the above list looked normal.

Uncle Peter · 17-12-2006, 13:42

Hmmmm unless dhcpd or the arp cache at your ubr is stuffed. Anything in your router log pages?

andy.j · 17-12-2006, 18:49

The only thing logged by the router was this:

0|DHCPC :Retry
1|DHCPC :Retry
2|DHCPC

iscovery
3|DHCPC

iscovery OK
1|DHCPC :Retry
2|DHCPC

iscovery

and everything was fine.

Uncle Peter · 17-12-2006, 19:42

That's pretty inconclusive then really. You would need to see what's coming back from the ubr which is not an option unless you can put a probe on your wan port.