"NotMe" <me@privacy.net> hath wroth:
>Cable company replaced our modem with a AMBIT Model U10C018
<http://support.cox.com/sdccommon/asp/contentredirect.asp?sprt_cid=74fc51f6-2b3c-4a96-a6b7-90e4e321738a>
>We have two Buffalo WHR-HP-G54 (Standard OEM software) and a Linksys
>WRT54GV5 (Standard OEM Software)
Are these operating as routers or access points? Specifically, do you
have the CAT5 cable to the modem connected to the 4 LAN ports on the
back of these boxes, or to the single WAN(internet) port? Is there a
hub or ethernet switch you didn't mention?
>All were individually working( one on line the rest spares) with the
>previous cable modem (Motorola S5100). None work with the current modem.
The Ambit looks like an almost exact replacement for the S5100. Unless
you have some kind of MAC address authentication game thanks to your
unspecified cable provider, it should work without any changes.
In order to figure out what to do, I need some clue as to how they
were setup. Specifically, I need the IP layout, which is probably the
culprit. Both your old S5100 and new Ambit are modems and do not have
built in NAT. The responsibility for obtaining an IP address is in
the router(s). However, you cannot have BOTH routers getting
individual IP's from your unspecified cable provider at the same time
unless you made arrangments to do so with the cable provider. I can
make an astute guess as to how it was setup if you would disclose how
you have the two routers wired to the modem.
>We have all the usual idiot lights working but no communication. buffalo
>software indicates that it sees the AMBIT modem but is unable to talk to the
>AMBIT modem.
That means the CAT5 cable connecting the two is working, but the IP
addresses are probably wrong.
>Cable support has no clue (they tried but have limited data on the AMBIT)
>Ambit support will not talk to the end user.
Did your unspecified evil cable company just mail you the modem or did
an installer deliver and install it? If the latter, they usually try
it before leaving. Let's do some testing.
1. Turn off everything except the modem and one laptop.
2. Run a CAT5 cable between the PC ethernet port and the modem.
<http://support.cox.com/sdccommon/asp/contentredirect.asp?sprt_cid=47887c69-d799-44ed-8165-3260010dcdcc>
3. Unplug the wireless boxes.
4. Power cycle the modem to clear the old MAC addresses.
5. Can you surf the internet this way? If so, the modem is working
as advertised. That leaves your two wireless boxes as the likely
culprit.
>Cable company says the soonest I can get a replacement modem is sometime
>next week.
Test the one you have with a direct connection as itemized above. If
that works, you don't need a new modem.
>BTW both Buffalo units and the Linksys work at other locations but different
>cable modems.
Work as routers or as access points (router disabled). I need to know
how you have it wired to determine if you've missed something.
>We have web access but only with the CAT5 connected to the cable modem one
>box at a time so we're not dead with regards to internet access but having
>to wait in line is a bit of a problem. (Not unlike bath room access when
>the grand daughters & friends are visiting.)
Never mind the test. Looks like the modem is working. I'll assume
that the WHR-HP-G54 is the box that's acting as a router. Make life
simple and try testing just this one box:
1. CAT5 cable from the internet port on the WHR-HP-G54 to the
ethernet port on the Ambit modem.
2. CAT5 cable from a working PC ethernet port to one of the 4 LAN
ports on the back of the WHR-HP-G54. You can do this via wireless,
but it just adds more complications.
3. Go to the "status" page on the WHR-HP-G54 and see if it displays
routeable IP addresses. If not, hit the "disconnect" and "connect"
buttons. Check the log file for errors. The usual problem is MAC
authentication.
4. If you've "cloned" the MAC address in the router, the ISP may have
the wrong MAC address, especially if your initial connection with the
new modem was NOT with the same PC you're using to test. If your
unspecified ISP uses MAC address authentication, call support and have
them reset the ARP table for your connection, or just wait about 15
minutes, with the modem disconnected, for it to reset.
>The issue is not critical but I would like to know what the problem and
>potential solution might be.
Hard to tell from here without numbers.
--
Jeff Liebermann
jeffl@cruzio.com
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Problem with a cable modem 
Linear Mode
