"WAN: disabled" when connecting router to cable modem

Question

I am trying to set up internet access with a Linksys WRT54G router (DD-WRT, set as a AP) and a Motorola/Arris SB6121 cable modem which uses WOW!. The problem is that the router can’t connect to the Internet via the cable modem. At the top of the router management page, the router always reports:

WAN: disabled

The signal lights on the cable modem are all OK (blue) except the last one (internet), which is a blinking orange/yellow. The computer can see the router management page, but not the cable modem page (192.168.100.1).

If I connect the router directly to the computer, then internet connection works fine, and I can see the modem management page (192.168.100.1). I have used this router in the past few years to get Internet connection without a problem.

All above is with wired connections.

Has anyone had similar issues and does anyone know a solution?

Solution

If I connect the router directly to the computer, then internet connection works fine, and I can see the modem management page (192.168.100.1).

In my experience, all cable modems from all cable ISPs are tied to a computer/devices MAC address when initially setup and then need to be reset to allow any new MAC addresses to connect to that modem.

Which means, when you state you can connect the cable modem directly to the computer and you can connect it’s because the Motorola/Arris SB6121 modem is tied to that MAC address.

So what you need to do is connect to the cable modem and reset it and disconnect the Ethernet cable right away from your system the second you do that. And then when the modem fully resets, go and connect the modem to your Linksys WRT54G router.

According to what I know about the Motorola/Arris SB6121, you can do this by going to 192.168.100.1 and clicking the “Configuration” option. The direct URL to this page should be:

http://192.168.100.1/cmConfig.htm

Near the bottom of that configuration page should be a button that reads “Reset All Defaults” with the message:

Resetting the cable modem to its factory default configuration will remove all stored parameters learned by the cable modem during prior initializations. The process to get back online from a factory default condition could take from 5 to 30 minutes. Please reference the cable modem User Guide for details on the power up sequence.

This is what you want it to do; you want to “remove all stored parameters learned by the cable modem” to allow a new MAC address to be associated with the Motorola/Arris SB6121 modem.

So click that “Reset All Defaults” button, and then once you have confirmation that the reset process is happening, disconnect the Ethernet cable from that modem to your computer and just let the modem recycle and get set up again. Could take a few minutes; just watch the lights.

Then when the lights are back to what you know as normal, connect the Ethernet cable from the Motorola/Arris SB6121 modem to the WAN port on Linksys WRT54G router and you should be good to go.

All that said, some cable ISP providers require you contact them to associate a new MAC address with a modem. Sometimes it’s as simple as logging into your cable ISP provider’s website to manage your account and adjusting something there. Or calling up the cable ISP provider directly to get things done.

But when all is said and done, this is a MAC address association problem. And once that is resolved and your Linksys WRT54G router is recognized as the valid/new MAC address associated with the Motorola/Arris SB6121 modem you are good to go.

Comments

[tinlyx]

Thanks a lot for your answer. I tried to "Reset All Defaults". It returns instantly without a progress bar or anything. How long will it take for the confirmation for the reset process to show?

[Giacomo1968]

@tinlyx “How long will it take for the confirmation for the reset process to show?” I don’t know. But my advice is just have the modem right in front of you, hit the “Reset All Defaults” in the browser, disconnect the Ethernet and then watch all the lights. Or from what I know of that model modem, you can just unplug it from the Ethernet connection as well as the AC power and wait a bit—like 5 minutes to an hour—and then power it up again to reset it. But the overall idea is to disconnect it from your PC so when it resets itself it doesn’t reassociate the MAC address from your PC again.