USB networking MAC regression (aka the usb0 -> eth0 change)

Nicolas Cavallari batchman at
Sat May 23 17:05:34 CEST 2009

For a while, I used to use USB networking to connect my FR to the interwebs.

I wanted to be able to connect my moko to any computer and let my entire LAN talk to it,
so instead of using masquerading or routing, i used the much simpler bridge mechanism,
to bridge my FR with my network.

This worked fine during the usb0 phase. But since the distro started using the official
MAC address, This wouldn't work anymore.

I traced this problem down to the fact that both the host NIC and the device NIC share the
same mac address. I wonder if this is a deliberate change (i hope not), because this not only break
bridging, but it would break many other advanced network configurations.

The bridge fails because it consider the host mac address to be a local mac (brctl showmacs) and
so ignore any host with the same mac. Changing the host mac address (with ifconfig ethXXX hw ether)
solves the problem, but it clearly not a acceptable solution.

What should i do instead ? Should i report this as a bug ?

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