new cable modem with one e-net port; router not working..

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Please tell me I'm not crazy and that things like this can
happen. And then hopefully, someone can come up with an answer
that will let me keep yesterday's status..

Apologies for not listing the exact model numbers. If it'll
help, I can get them later tonight. Note that there's no
other option for this specific router.

Connectivity: Charter cable -> new DOCSIS III cable modem
             with one e-net port out the back.

This morning: older DOCSIS II w/one port -> T-Mobile branded
             Linksys router [a], which supported 4-enet ports
             and 802.11 Wifi.

Now... the new cable modem lets me hook up _one_ computer directly
        via the e-net port. Or, make that, any one of four [b] computers
        directly. But... when I plug the router in they don't talk
        to each other and the router doesn't get an IP address
        So while I can hook the computers to router, both via the
        e-net ports and wifi, and they'll communciate
        with each other, they can't get out to the world.

(the IP address shows up on the Linksys screen as 0.0.0.0,
with similar useless defaults everywhere else).

So for now... I've got a Mac Mini hooked up past the cable modem,
taking in the e-net signal and sharing it out over WiFi. Works fine
for a limited time. But I'd really like to see if there's a way
of getting the Linksys to work (see [a] below).

So the first question: Am I insane or does this sort of stuff
happen? Note that I've tried using one of my spare (same model)
Linksys units, have done the whole DHCP release/renew, even
cloned the MAC numbers from one of the working computers to
the Linksys. Lots of power recycling, etc. All no good.

Suggestions? Thanks.

[a] it's a five or more y/o T-Mobile branded Linksys
which I'd like to stay with. Reason: It supports TM's
version of a VOIP phone line. Place SIM card in the
router, and it feeds an almost normal VOIP wired phone
circuit out the back. TM no longer offers this service
and I'm grandfathered in.

Oh, and the Mac Mini only has the one e-net port, so I
can't do any hard wiring..

[b] First was a Windows XP netbook for use in the initial
configuration. (I've had bad experience when using non Windows
machines in the past with this). Then a Mac laptop. Then
a Windows XP desktop. Lots of moving enet wires around.

Finally wound up using that Mac Mini.

- Thanks again.

_____________________________________________________
Knowledge may be power, but communications is the key
              dannyb@panix.com
[to foil spammers, my address has been double rot-13 encoded]

Re: new cable modem with one e-net port; router not working..
wrote:

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(...)

You are crazy and everything works as advertised.  Right.

You forgot the first step in troubleshooting... you need to blame
someone or the problem can't be fixed.  Anyone will suffice, as long
as it's not yourself, or anyone that might help you fix it.

The problem is that when you juggle routers and Mac Mini boxes around,
the unspecified model cable modem doesn't detect the change in MAC
address unless you power it down, and bring it back up again with
every change.  Also, check your settings on your unspecified model
T-Mobile branded router on the WAN (internet) port.  It should be set
to DHCP.  Also, do NOT clone the MAC address in the router config.  It
should show the MAC address of the router, not the MAC address of the
connected PC.



--  
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

Re: new cable modem with one e-net port; router not working..

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Oh, Ive done that...  

Quoted text here. Click to load it

It is.  

Oh, the Cisco DOCSIS is a DCP 3008. The TM/Linksys is a wrtu545g-tm.
The latter is a specially designed offshoot of the basic linksys
which includes the aformentioned pseudo/voip phone line output,
so the software is customized. I have absolutely no idea if
anything like dd-wrt could be added to it, and if it was, the
chances ar 99.9 percent the phone line would be toast.

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I've used both semi random MAC addresses and I've also used
the one from a computer that worked ten minutes earlier. (I
disconnected that computer from the system and had totally
different units).

- someone else suggested that I should try a "cross over"
ethernet cable. It's been a decade since that was something
to consider so I completely forgot about that possibility.

Now to see if I even have one....

Thanks to everyone for your suggestions.

- One option may be to get a different DOCSIS III cable modem.
I spoke with a local store here and they agreed I could try
it out and, if it didn't work, return it for full credit.

Charter's was free (yes, really... although I understand
they do charge in other areas) but I'm willing to eat
the expense if it works.

But first to try finding a cross over e-net cable. Those
were usuaally red, right? (I don't have any test equipment
or crimpers here).

Thanks again.
--  
_____________________________________________________
Knowledge may be power, but communications is the key
             dannyb@panix.com  
[to foil spammers, my address has been double rot-13 encoded]

Re: new cable modem with one e-net port; router not working..
[snippeth]

Thanks for the suggestions here, and also to the folk at Panix.

It turned out that using a cross-over cable I picked up
at Staples (which was yellow... ) did the trick.

Curiously it worked the first time. Then when I moved
things around with power cycling, it didn't. But it did
work the third, fourth, and now the final fifth time.

Thanks again.


--  
_____________________________________________________
Knowledge may be power, but communications is the key
             dannyb@panix.com  
[to foil spammers, my address has been double rot-13 encoded]

Re: new cable modem with one e-net port; router not working..
wrote:

Quoted text here. Click to load it

I can't imagine why, unless your other cable was simply bad and your devices
are capable of Auto MDIX, the capability to detect a crossover versus
straight through cable and adjust accordingly.

BTW, there is no standard color code for crossover cables.

Quoted text here. Click to load it

In that case a straight through cable should work equally well.


Re: new cable modem with one e-net port; router not working..

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Back in the Early Daze, the cross overs tended to be red.
Not a hard and fast rule, but that's what we expected.

Quoted text here. Click to load it


For the hell of it I tried again with a straight through
while moing things around. No goodsky.

'tiz a puzzlement.


--  
_____________________________________________________
Knowledge may be power, but communications is the key
             dannyb@panix.com  
[to foil spammers, my address has been double rot-13 encoded]

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