Subject: Re: RFC: bridge get fdb by bridge device

From: Jamal Hadi Salim <[email-masked]>
Date: Tue, 11 Feb 2014 16:08:55 -0500

On 02/11/14 16:00, Vlad Yasevich wrote:
> On 02/11/2014 03:15 PM, Jamal Hadi Salim wrote:

>
> Because it just a multi-function nic that isn't tagged with any
> kine of bridge flag.  As John said, this might be useful, but not
> done yet.
>

Ok, fair enough. Someone should send a patch - John perhaps.

>
> Not directly.  However, if you put a layered software device in between
> (vlan, bond, macvlan), then you can add that device to another bridge.
> In fact, people do that to get GVRP working with VMs.
>

Do you recall the reasoning behind it?

>> It certainly has some equivalent semantics (looks at dst MAC then
>> picks the port). Possible to add Vlans as well?
>
> I suppose.   You can do things like:
> # ip link add link eth0 dev vlan100 protocol 8021Q id 100
> # ip link add link vlan0 dev mac100 type macvlan
>
> Now, you have a macvlan (mac100) that will only receive vlan100 traffic.
> Expressing this in terms of fdb would be a bit difficult since each
> interface is separate and eth0 doesn't really know about the stack.
> It would require quite a lot of code.
>

nice.

>> Why dont we tag such a thing as a bridge then?
>>
>
> Because they are not always a bridge.  It could be just a nic capable of
> mac filtering.
>

I think in one of the modes it is merely a filter.
But you turn on this other feature it is a bridge.

>
> Didn't realize it has different connotation for vxlan.  The you probably
> don't want to include and support in the bridge fdb show command.

Thats what i thought you said earlier ;->

cheers,
jamal