cable modem mac address

[cdoc]

Hello
I apologize in advance as I am sure this question has been asked a
thousand times but I could not find the exact answer I was looking for
googling.
I helped someone setup a router on a cable modem today and had to clone
the mac address to get it to work.
Cable provider is Comcast. Modem Surfboard SB4100.
Is there a way to force the modem to reset to a new mac address?

 

[kony]

Hello
I apologize in advance as I am sure this question has been asked a
thousand times but I could not find the exact answer I was looking for
googling.
I helped someone setup a router on a cable modem today and had to clone
the mac address to get it to work.

Ok so now it works, but what exactly is it, which
functionality works and which does not?

Cable provider is Comcast. Modem Surfboard SB4100.
Is there a way to force the modem to reset to a new mac address?

Have you power cycled everything? Turn it all off then turn
on modem, router, and then boot the PC.

Shall we assume this location previosly had (Comcast) cable
internet access working with the SB4100 and the only thing
changed is the introduction of the router instead of a
(computer of some sort, commonly a Windows based PC)
connected directly to the SB4100?

Describe what isn't working. IIRC the SB4100 also has a
status feedback through the HTTP access, possibly @
http://192.168.100.1/ . It might have a page that lists
something like "Known CPE MAC Address", which would be the
router MAC address as shown on the router's information page
mentioned next, though you dont' set that, the modem should
detect it.

Similarly the router will have a page, often default is
http://192.168.0.1/ but if different should be listed in the
manual. These two configuration pages should show whether
they are operational.

If they work and it's merely the PCs that can't access the
internet, check their "IPCONFIG /all" at a command prompt.