Re: bnx2 vlan issue

[Seblu <seblu@seblu.net>]

On Wed, Mar 23, 2011 at 12:19 AM, Jesse Gross <jesse@nicira.com> wrote:
> On Tue, Mar 22, 2011 at 3:59 AM, Seblu <seblu@seblu.net> wrote:
>> On Tue, Mar 22, 2011 at 3:05 AM, Jesse Gross <jesse@nicira.com> wrote:
>>> On Thu, Mar 17, 2011 at 4:22 PM, Seblu <seblu@seblu.net> wrote:
>>>> On Thu, Mar 17, 2011 at 8:16 PM, Jesse Gross <jesse@nicira.com> wrote:
>>>>> On Thu, Mar 17, 2011 at 11:02 AM, Seblu <seblu@seblu.net> wrote:
>>>>>> On Thu, Mar 17, 2011 at 3:51 PM, Seblu <seblu@seblu.net> wrote:
>>>> How can I create a bridge with the untagged vlan from an interface?
>>>>
>>>>> * bridge on interface, vlans on bridge device.  This gives you a
>>>>> bridge with all packets and vlan devices can give you specific vlans.
>>>> I cannot use this schema, i used bridge to bring together vnet
>>>> interface and vlan interface.
>>>
>>> I'm not sure I understand why you say you can't use this.  You can
>>> combine vlans and bridging pretty much arbitrarily, including stacking
>>> multiple layers.
>> I don't see _how I can bridge an interface with an untagged vlan from
>> another interface_.
>>
>> I little example is maybe more clear:
>> My dekstop have 2 NIC (eth0, eth1). I receive from network admin 2
>> vlans. 20 untag and 21 tagged. My laptop is plugged to eth1.
>> I want "export" untagged vlan 20 to eth1.
>> Before 2.6.37, i do something like br0 = (eth0 + eth1). I put an ip on
>> br0 and on eth0.21. And br0 just have untagged frame from eth0 which
>> was transmitted to eth1. eth0.21 have only tagged frame from vlan 21.
>> eth1 did not receive tagged vlan 21.
>> After 2.6.37, i can do a bridge like before (br0 = eth0 + eth1) but i
>> must use br0.21 to have access to vlan 21 network in my desktop. But,
>> my laptop can also access to tagged vlan 21, and i don't want this.
>>
>> A lot of old xen based setup use this behaviour.
>> About my kvm test, I'm looking to the pci passtrough and macvtap, but
>> this requires configuration that supports it.
>> Why cannot have a eth0.U with only untagged frames?
>>
>>>
>>>>
>>>>> * Use ebtables rules in the bridge to accept/reject certain packets as desired.
>>>> I don't see how use ebtables to push untagged frame to a dedicated
>>>> iface which can be added in a bridge.
>>>
>>> You could have a bridge on the raw interface and connect all of the
>>> VMs that need untagged traffic.  If you add an ebtables rule to reject
>>> tagged traffic then vlan devices on the interface will continue to
>>> work as before.
>>>
>> If I ignores the fact that the name of the card is not fixed, i see.
>> But performance will follow? I don't believe this kind of config will
>> allow ~7/8Gbit/s of traffic.
>> Traversing ebtables rules is not free. And starting filtering traffic
>> is a really different job than just bridge cards together.
>
> I don't necessarily disagree that there should be a better way to do
> this, though as of the moment the above is probably your best bet.
>
> To me, the most important thing is to have consistent behavior across
> different cards.

Speaking of that, i've tryed  2.6.38 on my station (dell opitplex 980)
to use the new bridging schema and it doesn't work.
Exactly the case previously described: ip on br0 (eth0+eth1) and ip on
br0.42. eth0 driver is e1000e and eth1 is tg3. br0.42 don't receive
traffic.
I have to open a bug report?


> In 2.6.37 that behavior was standardized on the way
> non-accelerated NICs used to do but the other way is more common and
> perhaps better.  Eric B. posted a patch yesterday that better unifies
> the code paths.  This would be the first step to such a change because
> it would make it easier to move the handling logic for both at the
> same time.
Agree it's going in the right direction, but it's sad that breaks
basic network concept. Therefore hope in future versions.

Regards,

-- 
Sébastien Luttringer
www.seblu.net