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Date: Tue, 20 Apr 2021 13:38:09 +0200
From: Kurt Jaeger <pi@freebsd.org>
To: net@freebsd.org
Subject: source of ether address for tap0 ?
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Hello,

does anyone know how the system selects the MAC/ether adress of a
newly-created tap0 device ?

ifconfig tap0 create

has this:

tap0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=80000<LINKSTATE>
        ether 58:9c:fc:10:98:02
        groups: tap
        media: Ethernet autoselect
        status: no carrier
        nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>

How is that selected ?

We had a case where two devices selected the same ether/MAC...

-- 
pi@opsec.eu            +49 171 3101372                    Now what ?