Subject: Re: [PATCH net-next 0/4] Allow bridge to function in non-promisc mode

From: Vlad Yasevich <[email-masked]>
Date: Wed, 13 Mar 2013 11:45:40 -0400

On 03/13/2013 11:39 AM, Stephen Hemminger wrote:
> On Wed, 13 Mar 2013 08:12:29 -0400
> Vlad Yasevich <[email-masked]> wrote:
>
>> On 03/13/2013 02:22 AM, "Oleg A. Arkhangelsky" wrote:
>>>
>>>
>>> 13.03.2013, 05:45, "Vlad Yasevich" <[email-masked]>:
>>>
>>>> The series adds an ability for the bridge to function in non-promiscuous mode.
>>>
>>> What is the practical applications for such setup? In other words,
>>> in which cases I would want to put bridge into non-promiscuous
>>> mode and specify some uplink ports?
>>>
>>
>> On of the applications would be when bridge is an edge device servicing
>> a VM deployment.  Each of the VMs knows the mac address that the guest
>> has and may program that mac onto the uplinks.
>
> Why wouldn't that environment just use macvlan?
> Is it because changing libvirt is harder than changing the kernel?
>

No, because macvlan has a drawback that it doesn't easily let guests 
talk to the host.  Bridge is still most commonly used for just that reason.

-vlad