Re: About bridges

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

Staffan Thomén <staffan%shangtai.net@localhost> wrote:

>I was toying with bridging three of the four ethernet ports on an
>pcengines apu4d4 recently and bumped into something that made me unsure
>if I understood how to use bridges correctly.
>
>My setup is like this:
>
>wm1 configured with an address
>wm2 no address, just up
>wm3 same as 2
>
>and the bridge:
>
>brconfig bridge0 add wm1 stp wm1 add wm2 stp wm2 add wm3 stp wm3
>
>This all works, packets flow and addresses are learned on all
>interfaces, but ONLY if there is a cable with a link on wm1. It seems
>to be that if there is no link on wm1 the interface (status: no carrier
>and address shows <DETACHED>) gets disabled in the bridge, which kind
>of sucks because then the host has no address and communication stops.

[snip]

>So how is this supposed to work? Can I force the interface with an
>address to stay enabled somehow or is there a pseudo-device that I
>haven't found that I should be using?

It isn't supposed to work, an explicit change was made to the bridge
driver to make it behave like that.

The fix would be to revert the change, I have been bitten by it in
another way.

We probably want to move this discussion to the tech-net%NetBSD.org@localhost
list, could you repost your message there ?