Re: [nvo3] BFD over VXLAN: Trapping BFD Control packet at VTEP

[Greg Mirsky <[e-mail]>]

Hi Dinesh,
I greatly appreciate your comments. Please heave a look at the attached
copy of the working version and its diff to -07 (latest in the datatracker).

Regards,
Greg

On Tue, Oct 22, 2019 at 9:52 PM Dinesh Dutt <[e-mail]> wrote:

> I have the same feeling as Anoop. Greg, can you please point me to the
> latest draft so that I can quickly glance through it to be doubly sure,
>
> Dinesh
>
> On Wed, Oct 23, 2019 at 4:35 AM, Anoop Ghanwani <[e-mail]>
> wrote:
>
> Greg,
>
> I think the draft is fine as is.
>
> I discussion with Xiao Min was about #3 and I see that as unnecessary
> until we have a draft that explains why that is needed in the context of
> the NVO3 architecture.
>
> Anoop
>
> On Tue, Oct 22, 2019 at 11:17 AM Greg Mirsky <[e-mail]>
> wrote:
>
>> Hi Anoop, et al.,
>> I agree with your understanding of what is being defined in the current
>> version of the BFD over VxLAN specification. But, as I understand, the WG
>> is discussing the scope before the WGLC is closed. I believe there are
>> three options:
>>
>>    1. single BFD session between two VTEPs
>>    2. single BFD session per VNI between two VTEPs
>>    3. multiple BFD sessions per VNI between two VTEPs
>>
>> The current text reflects #2. Is WG accepts this scope? If not, which
>> option WG would accept?
>>
>> Regards,
>> Greg
>>
>> On Tue, Oct 22, 2019 at 2:09 PM Anoop Ghanwani <[e-mail]>
>> wrote:
>>
>>> I concur with Joel's assessment with the following clarifications.
>>>
>>> The current document is already capable of monitoring multiple VNIs
>>> between VTEPs.
>>>
>>> The issue under discussion was how do we use BFD to monitor multiple
>>> VAPs that use the same VNI between a pair of VTEPs.  The use case for this
>>> is not clear to me, as from my understanding, we cannot have a situation
>>> with multiple VAPs using the same VNI--there is 1:1 mapping between VAP and
>>> VNI.
>>>
>>> Anoop
>>>
>>> On Tue, Oct 22, 2019 at 6:06 AM Joel M. Halpern <[e-mail]>
>>> wrote:
>>>
>>>>  From what I can tell, there are two separate problems.
>>>> The document we have is a VTEP-VTEP monitoring document.  There is no
>>>> need for that document to handle the multiple VNI case.
>>>> If folks want a protocol for doing BFD monitoring of things behind the
>>>> VTEPs (multiple VNIs), then do that as a separate document.   The
>>>> encoding will be a tenant encoding, and thus sesparate from what is
>>>> defined in this document.
>>>>
>>>> Yours,
>>>> Joel
>>>>
>>>> On 10/21/2019 5:07 PM, Jeffrey Haas wrote:
>>>> > Santosh and others,
>>>> >
>>>> > On Thu, Oct 03, 2019 at 07:50:20PM +0530, Santosh P K wrote:
>>>> >>     Thanks for your explanation. This helps a lot. I would wait for
>>>> more
>>>> >> comments from others to see if this what we need in this draft to be
>>>> >> supported based on that we can provide appropriate sections in the
>>>> draft.
>>>> >
>>>> > The threads on the list have spidered to the point where it is
>>>> challenging
>>>> > to follow what the current status of the draft is, or should be.  :-)
>>>> >
>>>> > However, if I've followed things properly, the question below is
>>>> really the
>>>> > hinge point on what our encapsulation for BFD over vxlan should look
>>>> like.
>>>> > Correct?
>>>> >
>>>> > Essentially, do we or do we not require the ability to permit
>>>> multiple BFD
>>>> > sessions between distinct VAPs?
>>>> >
>>>> > If this is so, do we have a sense as to how we should proceed?
>>>> >
>>>> > -- Jeff
>>>> >
>>>> > [context preserved below...]
>>>> >
>>>> >> Santosh P K
>>>> >>
>>>> >> On Wed, Sep 25, 2019 at 8:10 AM <[e-mail]> wrote:
>>>> >>
>>>> >>> Hi Santosh,
>>>> >>>
>>>> >>>
>>>> >>> With regard to the question whether we should allow multiple BFD
>>>> sessions
>>>> >>> for the same VNI or not, IMHO we should allow it, more explanation
>>>> as
>>>> >>> follows.
>>>> >>>
>>>> >>> Below is a figure derived from figure 2 of RFC8014 (An Architecture
>>>> for
>>>> >>> Data-Center Network Virtualization over Layer 3 (NVO3)).
>>>> >>>
>>>> >>>                      |         Data Center Network (IP)        |
>>>> >>>                      |                                         |
>>>> >>>                      +-----------------------------------------+
>>>> >>>                           |                           |
>>>> >>>                           |       Tunnel Overlay      |
>>>> >>>              +------------+---------+       +---------+------------+
>>>> >>>              | +----------+-------+ |       | +-------+----------+ |
>>>> >>>              | |  Overlay Module  | |       | |  Overlay Module  | |
>>>> >>>              | +---------+--------+ |       | +---------+--------+ |
>>>> >>>              |           |          |       |           |          |
>>>> >>>       NVE1   |           |          |       |           |
>>>> | NVE2
>>>> >>>              |  +--------+-------+  |       |  +--------+-------+  |
>>>> >>>              |  |VNI1 VNI2  VNI1 |  |       |  | VNI1 VNI2 VNI1 |  |
>>>> >>>              |  +-+-----+----+---+  |       |  +-+-----+-----+--+  |
>>>> >>>              |VAP1| VAP2|    | VAP3 |       |VAP1| VAP2|     | VAP3|
>>>> >>>              +----+-----+----+------+       +----+-----+-----+-----+
>>>> >>>                   |     |    |                   |     |     |
>>>> >>>                   |     |    |                   |     |     |
>>>> >>>                   |     |    |                   |     |     |
>>>> >>>
>>>> -------+-----+----+-------------------+-----+-----+-------
>>>> >>>                   |     |    |     Tenant        |     |     |
>>>> >>>              TSI1 | TSI2|    | TSI3          TSI1| TSI2|     |TSI3
>>>> >>>                  +---+ +---+ +---+             +---+ +---+   +---+
>>>> >>>                  |TS1| |TS2| |TS3|             |TS4| |TS5|   |TS6|
>>>> >>>                  +---+ +---+ +---+             +---+ +---+   +---+
>>>> >>>
>>>> >>> To my understanding, the BFD sessions between NVE1 and NVE2 are
>>>> actually
>>>> >>> initiated and terminated at VAP of NVE.
>>>> >>>
>>>> >>> If the network operator want to set up one BFD session between VAP1
>>>> of
>>>> >>> NVE1 and VAP1of NVE2, at the same time another BFD session between
>>>> VAP3 of
>>>> >>> NVE1 and VAP3 of NVE2, although the two BFD sessions are for the
>>>> same
>>>> >>> VNI1, I believe it's reasonable, so that's why I think we should
>>>> allow it
>>>>
>>>> _______________________________________________
>>>> nvo3 mailing list
>>>> [e-mail]
>>>> https://www.ietf.org/mailman/listinfo/nvo3
>>>>
>>>