For VM there is no need to send AC (ESI) route since the notion of a
VNIC LAG doesn't make sense.  ESI route to indicate AC is used when
there is a need for multi-homing.  So specifically for a single VM
there is only MAC route.

On Wed, Sep 26, 2012 at 6:11 PM, Shah, Himanshu <[email protected]> wrote:
> Attachment Circuit to that EVPN instance may not exist either, when VM moves
> to different host.
>
> The need to sprout AC was noted in the NVO3 interim meeting as part of gap
> analysis on L2VPN based solution.
>
>
>
> /himanshu
>
>
>
>
>
> From: [email protected] [mailto:[email protected]] On Behalf Of
> Luyuan Fang (lufang)
> Sent: Wednesday, September 26, 2012 5:51 PM
> To: Sunny Rajagopalan; Lucy yong
> Cc: Kireeti Kompella; [email protected]
>
>
> Subject: Re: [nvo3] Push or pull?
>
>
>
> Ø  The RT could change when the VM moves, in case the VM moves to an NVE
> which wasn't previously subscribed to the VPN that the VM belongs to.
>
>
>
> Not correct. The RT does not change when VM moves, or it breaks VM mobility.
>
> When you move the VM to a new NVE which does not have the VPN the VM belongs
> to, the VPN/VRF/RT… need to be configured on the new NVE. The RT of the VM
> does not change.
>
>
>
> Don’t we need to config  the relevant VN/VPN on the new NVE which does not
> have it yet, regardless the model?
>
>
>
> Luyuan
>
>
>
> From: [email protected] [mailto:[email protected]] On Behalf Of
> Sunny Rajagopalan
> Sent: Wednesday, September 26, 2012 5:35 PM
> To: Lucy yong
> Cc: Luyuan Fang (lufang); Kireeti Kompella; [email protected]
> Subject: Re: [nvo3] Push or pull?
>
>
>
> There's two different topics being talked about here:
> Push, which can be optimized using RTs. RTs can be used to ensure that an
> NVE only receives routes for the VPNs it participates in. The RT could
> change when the VM moves, in case the VM moves to an NVE which wasn't
> previously subscribed to the VPN that the VM belongs to. Due to the state
> this creates in the route server, you would want to use it at a VPN-level
> granularity.
>
> Pull, which works by the NVE requesting the route server to "please give me
> endpoint information about address X in VPN Y". This doesn't result in
> additional state at the route server, and the route server doesn't push
> locators for any other end points in that VPN.
>
> I think we're reaching consensus that both are needed, right?
>
> --
> Sunny
>
>
>
>
> From:        Lucy yong <[email protected]>
> To:        "Luyuan Fang (lufang)" <[email protected]>, "Shah, Himanshu"
> <[email protected]>, [email protected], Kireeti Kompella
> <[email protected]>,
> Cc:        "[email protected]" <[email protected]>
> Date:        09/26/2012 02:22 PM
> Subject:        Re: [nvo3] Push or pull?
> Sent by:        [email protected]
>
> ________________________________
>
>
>
>
> OK, I see we have different interpretations on NVE to have all the endpoint
> route. My interpretation is that although an EVI provides the communication
> among the VMs in a closed use group, it is not necessary for a VM to
> communicate to all other VMs in the group at a time or all time, therefore
> having each NVE to maintain all the endpoint routes in an EVI is not
> necessary. This is the concern I got from Sunny's mail.
>
> Seem that you have different interpretation.
> Lucy
>
> -----Original Message-----
> From: Luyuan Fang (lufang) [mailto:[email protected]]
> Sent: Wednesday, September 26, 2012 4:00 PM
> To: Lucy yong; Shah, Himanshu; Thomas Narten; Kireeti Kompella
> Cc: [email protected]
> Subject: RE: [nvo3] Push or pull?
>
> Why does the VM need to change RT when it moves? Is not the VM supposed to
> stay in the same VPN and only changing location?
> The VM should keep the same RT in order to maintain the membership of that
> VPN it belongs to.
>
> Luyuan
>
>> -----Original Message-----
>> From: [email protected] [mailto:[email protected]] On Behalf Of
>> Lucy yong
>> Sent: Wednesday, September 26, 2012 4:48 PM
>> To: Luyuan Fang (lufang); Shah, Himanshu; Thomas Narten; Kireeti
>> Kompella
>> Cc: [email protected]
>> Subject: Re: [nvo3] Push or pull?
>>
>>
>>
>> Why do you want to change RT on the fly? Would not that create security
>> issues? (And peer group or ORF don't change RT on the fly anyway).
>> [[LY]] to support VM mobility. What is an interested endpoint moving
>> from one NVE to another?
>> lucy
>>
>> RT-rewrite can be done when inter-connecting the VPN across two ASes
>> which are (or were) administrated by different administrative domains,
>> but they are carefully controlled/designed and configured by the
>> operators on the ASBRs or RRs. No RT change on the fly as I know of.
>>
>> Luyuan
>>
>>
>> > -----Original Message-----
>> > From: Lucy yong [mailto:[email protected]]
>> > Sent: Wednesday, September 26, 2012 4:13 PM
>> > To: Luyuan Fang (lufang); Shah, Himanshu; Thomas Narten; Kireeti
>> > Kompella
>> > Cc: [email protected]
>> > Subject: RE: [nvo3] Push or pull?
>> >
>> > RT is easy to define different topology, but not flexible to changes
>> on
>> > fly. Peer group or ORF is more about filtering setting, it may better
>> > fit here.
>> > Lucy
>> >
>> > -----Original Message-----
>> > From: Luyuan Fang (lufang) [mailto:[email protected]]
>> > Sent: Wednesday, September 26, 2012 3:10 PM
>> > To: Lucy yong; Shah, Himanshu; Thomas Narten; Kireeti Kompella
>> > Cc: [email protected]
>> > Subject: RE: [nvo3] Push or pull?
>> >
>> > > in push model, BGP peer group or ORF may be used to avoid every NVE
>> > to have all endpoint routes;
>> >
>> > In BGP VPN case, it is most efficient to use RT Constraint [RFC 6484]
>> > for selective route distribution - only send the VPN routes to the
>> peer
>> > who has the relevant VPNs.
>> > Luyuan
>> >
>> >
>> > > -----Original Message-----
>> > > From: [email protected] [mailto:[email protected]] On
>> Behalf
>> > Of
>> > > Lucy yong
>> > > Sent: Wednesday, September 26, 2012 4:03 PM
>> > > To: Shah, Himanshu; Thomas Narten; Kireeti Kompella
>> > > Cc: [email protected]
>> > > Subject: Re: [nvo3] Push or pull?
>> > >
>> > > I agree with Thomas. Both "push" and "pull" models have their
>> > > application space. To add on two points, in push model, BGP peer
>> > group
>> > > or ORF may be used to avoid every NVE to have all endpoint routes;
>> in
>> > > the pull model, an NVE will have temporary caching to reduce the
>> > number
>> > > of queries.
>> > >
>> > > Lucy
>> > >
>> > > -----Original Message-----
>> > > From: [email protected] [mailto:[email protected]] On
>> Behalf
>> > Of
>> > > Shah, Himanshu
>> > > Sent: Wednesday, September 26, 2012 2:46 PM
>> > > To: Thomas Narten; Kireeti Kompella
>> > > Cc: [email protected]
>> > > Subject: Re: [nvo3] Push or pull?
>> > >
>> > > I kind of agree with Thomas.
>> > >
>> > > Cisco gave LISP (pull based) presentation which is a working model,
>> > > during NVO3 interim.
>> > > I believe there are several ways to skin a cat and we should not
>> > limit
>> > > our options.
>> > > Besides, I also got an impression from the chairs that discussing
>> > > preference of one solution over other is
>> > > rather premature based on where the NVO3 is.
>> > >
>> > > Regards,
>> > > himanshu
>> > >
>> > > -----Original Message-----
>> > > From: [email protected] [mailto:[email protected]] On
>> Behalf
>> > Of
>> > > Thomas Narten
>> > > Sent: Wednesday, September 26, 2012 2:04 PM
>> > > To: Kireeti Kompella
>> > > Cc: [email protected]
>> > > Subject: Re: [nvo3] Push or pull?
>> > >
>> > > Hi Kireeti.
>> > >
>> > > Kireeti Kompella <[email protected]> writes:
>> > >
>> > > > I'm glad you brought this up. Actually, this conversation has
>> > > > happened several times, to my knowledge, without a firm
>> > conclusion.
>> > > I
>> > > > doubt we can close it, but at least, let's air it.
>> > >
>> > > > Push: send route updates to everyone (first see Aldrin's comment
>> > > about
>> > > > RT Constraint) as soon as you (the AUTHORITY/ORACLE) get them.
>> > >
>> > > > Pull: sit on updates you get until someone asks for them.
>> > >
>> > > > I could try to convince you what a terrible idea Pull is. I could
>> > > > refer to the Internet, which is all Push, and scales reasonably
>> > well.
>> > >
>> > > You mean like DNS or ARP?
>> > >
>> > > I do not think we should say "push is good, pull is bad". That is
>> > just
>> > > too categorical a statement.
>> > >
>> > > > I could ask you what happens to packets while the Pull is being
>> > > > responded to, or a bunch of related questions. I won't.
>> > >
>> > > They get queued. Or dropped. Or possibly something else. Yes, there
>> > are
>> > > implications to that. But not necessarily a show stopper either.
>> > >
>> > > > > In my view, this puts an unnecessary load on NVEs.
>> > >
>> > > > Let's talk instead about the "unnecessary load". Can someone
>> > quantify
>> > > > this?  Is it CPU? memory? messaging? What's the bottleneck or
>> pain
>> > > > point?
>> > >
>> > > Some or all of the above.
>> > >
>> > > If typical VNs are smallish, I agree that an NVE can preload full
>> > > tables with no problem. But what about for very large VNs? Should
>> the
>> > > architecture *force* such preloading of full tables, even if the
>> > > working set of routes is actually very small?
>> > >
>> > > And what about for very large VNs where there is a lot of VM
>> > mobility?
>> > > Should all NVEs be required to get update info even for
>> destinations
>> > > they don't care about?
>> > >
>> > > > Here's my back-of-the-envelop calculation for memory, normalized
>> to
>> > a
>> > > > VM. Let's say a VM has 10,000 friends in the DC that it might
>> > > possibly
>> > > > want to talk to, but only one that it really wants to talk to.
>> > Let's
>> > > > say that a FIB route entry takes 100 bytes. That adds up to a
>> > > possible
>> > > > total of 1MB vs. an actual of 100 bytes. Is 1MB really something
>> > one
>> > > > should optimize, especially considering that the VM has probably
>> > been
>> > > > allocated 4GB?
>> > >
>> > > Are you really arguing that the difference between 1MB and 100
>> bytes
>> > > is just noise?                  And who says this is in conventional
>> > > memory on
>> a
>> > > host?
>> > > I could see this being done in the ASIC...
>> > >
>> > > > Maybe there is a dimension to this that really is an issue. I
>> would
>> > > > love to know, especially with numbers backing it up. But let's
>> > first
>> > > > convince ourselves that this is a problem worth solving before
>> > > > spending cycles solving it.
>> > >
>> > > I do not think we should today require that the NVO3 architecture
>> (in
>> > a
>> > > MUST sense) support only push. I think we should allow for either
>> > push
>> > > or pull, or some combination. I can see benefits with both
>> > approaches.
>> > >
>> > > Note also that we may be looking at the problem from different
>> > > perspectives. For example, in a single data center, I can imagine a
>> > > centralized directory service holding the complete address mapping
>> > > information for all the VNs in the DC. An NVE in such cases can
>> query
>> > > such a mapping system with very very low latency.
>> > >
>> > > Thomas
>> > >
>> > > _______________________________________________
>> > > nvo3 mailing list
>> > > [email protected]
>> > > https://www.ietf.org/mailman/listinfo/nvo3
>> > > _______________________________________________
>> > > nvo3 mailing list
>> > > [email protected]
>> > > https://www.ietf.org/mailman/listinfo/nvo3
>> > > _______________________________________________
>> > > nvo3 mailing list
>> > > [email protected]
>> > > https://www.ietf.org/mailman/listinfo/nvo3
>> _______________________________________________
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