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linuxnetwork-programmingethernet

MAC address randomly changes when bringing interface up


Every time I start my network interface, I get a different MAC address! If I try to force the MAC address value using

ifconfig usb0 hw ether AA:BB:DD..:FF

it will be again different after issuing

ifconfig usb0 up

What make this MAC address change? How can I stop this to happen and stick to HW burned MAC address?

I am using a panda board (omap4/armv7) on a angtrom distribution. The inteface is a smsc95xx USB 2.0 Ethernet.

Thanks, Fabrice.


Solution

  • There is an issue with the smsc95xx driver.

    [PATCH] smsc95xx: generate random MAC address once, not every ifup

    There is also something in the work to get a 'repeatable' MAC generation going, but it didn't get much uptake:

    Beagleboard xM smsc95xx MAC address from die id

    Edit just searching for smsc95xx mac address gives a ton of competing patches, with some more explanations (the smc hub+NIC frequently doesn't have an EEPROM, so also no MAC)