[ovs-discuss] Trunk port

[Ansis Atteka]

On Wed, Mar 21, 2012 at 8:17 PM, sonny sonny <sonny085 at gmail.com> wrote:

> Hi Ben,
>
> I think you are not getting my question.Sorry for the unclear query.
>
> I am saying if my set-up is following then why I am not getting reply of
> ping request, please let me know where I am wrong in this setup instead of
> changing this in other way. (commands used mentioned in first mail below)
>
>               VM1-------vnet0==OVS==vnet1------VM2
>
> now I have made vnet0 and vnet1 as trunk port with vlan 2( I can give more
> vlan also in this list) , br0 is trunk by default as per OVS feature.
> now when I am sending tag 2 ping request from VM1 by traffic generator
> then vnet0 should accept this because it is trunk for vlan 2,this ping
> request is receiving on VM2 (because vnet1 is also trunking vlan 2) but no
> ping reply is creating on vnet1 to send to vnet0.
>
I believe you are incorrectly understanding what is "access port" and what
is "trunk port". I would suggest reading
http://en.wikipedia.org/wiki/Trunking#VLANs to understand the analogy
between trunk port (thick cable that contain many wires) and access ports
(a single wire in that thick cable).

By the way trunk ports are called that way, because those thick cables
simply resemble elephant trunk (or nose) in older day telephony.

When you say that you want port with trunks=2, I think that what you
actually want to accomplish is to use access ports with tag=2 (as Ben
already suggested)? It does not make sense for me to use trunk port with
vlan_tag=2 unless you have imagined something like nested VLANs?


> -Sonny
> On Wed, Mar 21, 2012 at 9:52 PM, Ben Pfaff <blp at nicira.com> wrote:
>
>> If you want a trunk port to accept untagged packets then include VLAN 0
>> in the set of trunks.
>>
>> On Wed, Mar 21, 2012 at 08:51:17AM +0530, sonny sonny wrote:
>> > Thanks for your quick response.
>> >
>> > "tag" is working ,commands you have given I have already used and that
>> > works.
>> > But I want to work with trunk ports now and if port is trunk with vlan
>> 2 (
>> > we can specify particular vlan also to a trunk port)  then untagged
>> > packet/other vlan tag packet to trunk port will  drop.
>> >
>> > so If I am sending same vlan tag packet (vlan 2)  then why ping reply is
>> > not coming.
>> > how trunk with "particular vlan" specified will work in OVS? Am I
>> missing
>> > anything?
>> >
>> > -Sonny
>> >
>> > On Tue, Mar 20, 2012 at 9:43 PM, Ben Pfaff <blp at nicira.com> wrote:
>> >
>> > >  On Tue, Mar 20, 2012 at 03:09:12PM +0530, sonny sonny wrote:
>> > > > Hi All,
>> > > >
>> > > > I am using OVS 1.2.2 and have one OVS machine with two VMs.
>> > > > Following commands I have used -
>> > > >
>> > > >  Create an OVS bridge:
>> > > >  ovs-vsctl add-br br0
>> > > >
>> > > > Add eth0 to the bridge
>> > > > ovs-vsctl add-port br0 eth0
>> > > >
>> > > > Add VM1 as an “trunk port” on VLAN 2:
>> > > > ovs-vsctl add-port br0 vnet0 trunks=2
>> > > >
>> > > > Add VM2 on VLAN 2:
>> > > > ovs-vsctl add-port br0 vnet1 trunks=2
>> > > >
>> > > > now when I am sending tag 2 ping request packet from VM1 to VM2 ( by
>> > > > traffic generator) , then ping reply is not coming.
>> > > > Please correct me where I am wrong.
>> > >
>> > > If you add those as trunk ports, then the VMs have to add the tags
>> > > themselves.  Did you do this?  It involves the "vconfig" utility (or
>> > > "ip link add link type vlan").
>> > >
>> > > If you want OVS to automatically tag those packets, then you want
>> > > access ports instead.  Here are the commands that you would use:
>> > >        ovs-vsctl add-port br0 vnet0 tag=2
>> > >        ovs-vsctl add-port br0 vnet1 tag=2
>> > >
>>
>
>
> _______________________________________________
> discuss mailing list
> discuss at openvswitch.org
> http://openvswitch.org/mailman/listinfo/discuss
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://openvswitch.org/pipermail/ovs-discuss/attachments/20120321/15ab14b5/attachment.html>