1841 on a roadrunner modem

[joebagodoe]

I am setting up a 1841 router that the client already has with a low cost roadrunner cable connection. the 1841 he has was from a previous vendor with a T1. The 1841 does not have the cable modem card in it. I have tried quite a few things and I will attempt to list them. Firstly, I ensured the cable modem doesn't hold MAC addresses - I have connected my laptop to it and a Linksys router, and both times I recieve a WAN IP and can browse the intarweb.

I connected the modem to FE0/1 of the 1841 router, ensured it's admin up (pretty lights), set it to DHCP, but when I issue the "show ip interface brief" FE0/0 has my internal IP address, but FE0/1 isn't getting an IP. I thought that would be the simple part. before I did any of this, I formated flash, and loaded a new IOS onto the 1841 (c1841-adventerprisek9-mz.124-13a.bin). What am I missing?

[joebagodoe]

I was able to obtain a Cisco uBR905 cable modem and will try to get it up and running. At this point, it just seems that the cisco router cannot find the broadcast or isn't broadcasting the follow up DHCP request to my server. Maybe an actual cisco modem will do better.

[joebagodoe]

Here are the results of the Ethereal capture. I disabled DHCP on 192.168.0.2 (Win2k3 server) and enabled it on 192.168.0.1 (wrt54g router), but it still isn't obtaining an IP.

[paolo bevilacqua]

Hello,

I see the reply from dhcp server on linksys and it appears OK. Not sure why the router is not accepting it. Sometime I've seen router having some difficulty in accepting the address, but eventually it worked in any case.

Do you get a different address each time on the cablemodem, or it is always the same so that you can configure it statically in the router ?

[joebagodoe]

The IP on the cable modem is dynamic. He really doesn't want to upgrade to a static yet since he's not hosting anything.

I can't believe this is kicking my ass. This should be simple, but it just isn't working. I've checked for ios compatibility, and it's running 12.4.13b, which is an acceptable 1841 router ios.

I wish I could submit a bug report to cisco, but I don't have an actual account.