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

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, 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 [to foil spammers, my address has been double rot-13 encoded]

Reply to
danny burstein
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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.

Reply to
Jeff Liebermann

Oh, Ive done that...

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.

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.

Reply to
danny burstein

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.

Reply to
danny burstein

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.

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

Reply to
Char Jackson

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

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

'tiz a puzzlement.

Reply to
danny burstein Forums website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.