[CLUE-Tech] Cisco 678 Configuration

[Randy Arabie]

Quoting black at galaxy.silvren.com:

> That's pretty wild. Under the ARP section it complains about two invalid
> MAC addresses answering for 192.168.1.1, one after another and they are
> exactly 1 digit apart. That isn't a multicast MAC address, so it has
> absolutely no reason to be there. They also don't match the MAC address of
> the ethernet port on your Cisco 678.

Yup.  Wild is the word.  It makes me want to laugh, but I can't 'cause I'm just 
totally frustrated with this.  How can this happen?

> I'd guess that's the key to the whole situation. Any time a host on your
> home network tries to get to something out on the 'net it will have to
> send to your 678, and if someone else is answering ARP requests for that
> address, you'll have problems. Sorry if that came across as networking
> 101, I'd guess you already know that but I threw it in for completeness.
> :)
> 
> Are you sure there isn't something on your LAN assigned to that address?
> Doesn't seem likely since you said you connected directly to the 678 and
> it still didn't work.

Yes, that's exactly why I connected the laptop directly to the 678 via a 
crossover.  That way I would know there was nothing else there that could 
interfere with routing.

> Have you tried doing a traceroute from somewhere out on the Internet (dial
> in, perhaps) to your 678? I know you said Qwest can get to it, but if
> there's some bizarre routing problem between Qwest and where you're dialed
> in they'll not see it. This still won't explain the ARP weirdness,
> however.
> 
> You could also unplug the 678 from the network, try to ping 192.168.1.1
> and fire up ethereal to see if anything else is trying to answer for that
> address or sending back ARP replies.

I didn't try that, it's a thought.  To restate what you are suggesting, I would 
unplug the crossover from my laptop...which would leave it [laptop] connected 
to nothing.  I'm quite possitive I'll get no replies.  I understand what your 
thinking.  At one point, as my message indicates, I did have three LAN hosts 
connected to the 678 via a hub.  However, I reduced it down to just my laptop 
connected to the 678 via a crossover.

But, your suggestion does makes think.  I never checked the ARP table on my 
laptop.  But I doubt that's the problem 'cause I hooked up the old 486 Win95 
box to the router via the crossover and it didn't work either.  Nor did my 
wifes WinXP laptop, or my desktop running Libranet.

> If worse comes to worse you can just blow the configuration off the 678
> and start over. Maybe something is "stuck" in the config. This will be a
> lot easier than trying to put a new CBOS image.

I'll search the CISCO site for those instructions, I don't recall how to "blow 
the configuration".  I thought that's what my ISP did for me in the first 
place.  I left the 678 with them for a day last week to get it setup.  Maybe 
that's what they will do to it today.
-- 
Allons Rouler!

Randy
http://www.arabie.org/