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Re: agr(4) + bridge(4): problems!

On Fri, Sep 28, 2012 at 07:11:03PM +0100, Hugo Silva wrote:
> On 09/28/12 15:52, Manuel Bouyer wrote:
> >On Fri, Sep 28, 2012 at 09:57:11AM -0400, Thor Lancelot Simon wrote:
> >>On Fri, Sep 28, 2012 at 02:49:46PM +0200, Manuel Bouyer wrote:
> >>>
> >>>You mean, for agr+bridge ?
> >>>I suspect link1 is causing the issue you're seeing: without any LACP
> >>>negotiation, a packet going out by wm0 will be received on wm1, and
> >>
> >>Why?  wm0 and wm1 aren't in the bridge, and if you have LACP turned off
> >>entirely, the host on the other end must be configured so it doesn't
> >>reflect packets this way, either.
> >
> >But in his setup, if I understood it properly, the other end is a switch,
> >which probably can't deal gracefully with this setup.
> >
> It is indeed a switch without support for LACP. The manpage does say
> link1 disables LACP.
> Note that the network works fine on the dom0 using agr0, it's only
> when agr0 is on a bridge that problems appear (and even then the
> host's networking, running with agr0 as the primary interface, still
> works). I mention this because if the issue was just LACP, I can't
> see why the dom0 networking would work as expected.

Because (I guess, I've not looked at this part of the code) agr0 is filtering
its own mac address. But agr0 probably has no support to filter
foreign addresses that are known to the bridge (and even if it did, the
bridge's address expire mechanism would cause occasional duplicate
packets, I guess - or, worse, to register the address on the
wrong interface).

> So perhaps there is a unhandled situation somewhere? For instance,
> would agr(4) without link1 and bridge(4) work together?

I'd expect so.

Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference

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