[Bridge] Bridge interface always down since Linux >= 2.6.39
arnau at milkypond.org
Thu Jun 30 12:58:31 PDT 2011
> There are two flags, IFF_UP - admin up/down and IFF_RUNNING carrier
> up/down The IFF_UP is controlled manually, and IFF_RUNNING is what you
> are talking about.
Interesting, thank you very much for the explanation.
> In older kernel versions, the bridge device always asserted carrier
> even if all ports did not have carrier. Now it reflects the state of
> the underlying device. In your case the problem is that the tap
> interfaces aren't reporting carrier.
This is what I understood by testing with a real network interface
attached to the bridge, however I was not sure whether it was intended
or a regression. In this particular case, a tap interface is reporting
carrier when an userspace program is attached to it AFAIK, so I guess
there is nothing else I can do besides of attaching an userspace
Thanks for the quick response.
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