by Peter Ridge
I recently ran into a situation where a Linksys WRT-54G wasn’t able to get an IP address when connected to an Ambit/uBee U10C018 cable modem. This issue may also apply to other routers when used with the U10C018 cable modem.
When a PC is connected directly to the modem, everything works fine and the Internet can be reached normally. When a router is placed inbetween, then there is no longer any access to the Internet. Viewing the status information in the router shows that it is unable to acquire an IP address, even though the router is set to use automatic configuration via DHCP, the same as the PC.
Apparently, the U10C018 cable modem is aware of the MAC address of various routers. In order to get the router to work with the modem, use the MAC cloning feature of the router. The location of this option will depend on your particular router brand and model. When you find it, turn it on. Then, set the desired MAC address.
On the Linksys router, the MAC address cloning page has a button to copy the MAC from the PC that’s currently connected to the administration interface. If your router has this feature, use it to set the router to the same MAC address as your computer. If your router does not have this feature, then you’ll have to get your MAC from the network driver or the network card.
Once you have a non-router MAC entered into the MAC cloning setting, save and restart the router.
Have you run into this issue? If so, post your router model and steps to configure MAC cloning for it in the comments.
My Model Number Is: Linksys BEFW11S4
To configure mac cloning: enter router setup, select Mac Address Cloning and select clone.
This does not work for me.
@David: Cloning didn’t work? Does the modem work properly when you connect your computer directly to it?
I just ran into a similar situation with a different Ubee cable modem … but the problem is on the cable bonding side, not the modem. Hidden in my ISP support pages it says “the IP address is internally associated with the MAC address. If you remove the PC then attach a router, you MUST power cycle both the modem and the router for a new association”.
Original poster? did you power off/on both devices? Try it.
@Random Reader: Yes, tried power-cycling multiple times. Apparently, that one didn’t want to re-associate. Good tip, though. Could help others with their model of cable modem. Thanks!
I’ve also heard of cases where turning on the router before the modem will get them to cooperate.
I have a Belkin F5D8235-4 and it also would not associate an IP address from the modem. Cloning fixed the problem though.
Setup > Manual > Internet Wan > MAC Address Cloning > Clone
@Jesse: Thanks for the info on the Belkin F5D8235-4. Good to hear it worked for it too.
It seems like you can reset the MAC address the modem recognizes first by disconnected any ethernet conenected device. Then either reset it to factory defaults, then plug it into the Router, or power cycle it, then plug it into the router.
See if this works. Usually works for me when i have these issues. simpler than making changes in Router Settings.
UBee U10C018 cable modem D-Link DIR-655 Home network.
Directly connected PC to UBee modem first and this worked.
Did not have to clone PC MAC to router *BUT* did have to power cycle UBee modem _after_ D-Link DIR-655 router’s internet connection method was changed to Dynamic-IP-DHCP.
Cloning the MAC address of the PC to the router may also work but I did not try this and I think power cycling the modem _after_ the router is an easier way to try first. Just make sure the router is setup for Dynamic-IP or Static-IP (if you have asked for one from your provider).