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My ISP allows only one computer so I have to change the mac address.

On the other computer I use ubuntu and I've changed my mac address with both ifconfig and macchanger. The internet still doesn't work, it doesn't find the connection.

What should I do ?

I used this tutorial

Thank you

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up vote 1 down vote accepted

You can usually get around MAC address restrictions by power-cycling the cable or DSL modem (actually a router).

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I'm not sure, but maybe that fixed my problem, anyway ... good job – Horatiu Jeflea Dec 9 '10 at 0:08
I'd expect that in most cases it's not the modem that is limiting this, but some remote equipment at the provider. So if this works, then probably restarting the connection makes the provider flush the MAC address it knows for that connection? Also, I doubt one would classify such a dump modem as a router. Not too much to route if it only accepts a single MAC? – Arjan Dec 9 '10 at 0:17
Definition of a router: connect two IP (or other) networks. Many cable modems most definitely do lock onto one MAC address, and refuse to accept another until power-cycled--that's just true and not debatable. – CarlF Dec 9 '10 at 5:18

Here's the glory of routers. You can set the mac address on most routers (atleast the ones you flash with dd-wrt, only ones I'm experienced w/ lately). Using a router to manage your internal network (and split your internet connection to multiple computers/devices), you should be able to make it work.

Your ISP will only see the router connected to the connection and hence only one MAC address and your router will split the rest of the connection.

This worked wonders in college where the dorms were only allowed to have one connection and it was 'tied' to the MAC address that they 'checked' at the beginning of the semester. 'Spoof' the MAC address on your router and you're all set :)

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