Re: draft-van-beijnum-multi-mtu-05.txt

[Sowmini Varadhan <[e-mail]>]

On Wed, Apr 6, 2016 at 12:55 PM, Erik Nordmark <[e-mail]> wrote:

On 4/6/16 12:18 PM, David Lamparter wrote:
>
>> On Mon, Apr 04, 2016 at 11:37:17PM +0200, Mikael Abrahamsson wrote:
>>
>>> I'll be presenting
>>> https://tools.ietf.org/html/draft-van-beijnum-multi-mtu-05 in 6man on
>>> Wednesday. There are operational considerations here, so I encourage
>>> people to drop in and/or comment on this draft.
>>>
>> Ok... easy comments/opinions first:
>> - should definitely be ICMP, not UDP.  Erik Nordmark's suggestion to
>>    piggyback on NUD sounds great, though admittedly I haven't thought it
>>    through looking for pitfalls.
>>
> One issue compared to a dedicate probe is that a NUD (a unicast NS) of
> size X wouldn't necessarily result in a unicast NA that is also padded;
> perhaps one can add such behavior so that we can get the bidirectional
> probe in both directions.


there's also the question of what mtu to advertise in the face of
pvlans, when there is a router on a promisc port proxying the NA.

In practice, since a node typically uses a single interface to talk
to multiple onlink neighbors, and jumbo mtu etc is configured per
interface, you would end up getting metered down to the lowest
common denominator for the subnet, right?

--Sowmini