> [JORGE] 2 ACs on the same ESI/EVI on the same PE? I suppose to are talking
> about VLAN-aware bundle interfaces, where each VLAN goes to a different BD?
> note that the proxy-arp/nd function is per broadcast domain, i.e. one per EVI 
> for
> VLAN-based and VLAN-bundle and one per BD for VLAN-aware bundle
> interfaces. We can clarify that in the draft.

 [Tony saiz:]  same EVI/ESI/VLAN which for me indicates that the two ACs belong 
to the same customer and are same  ether. very small nitpick, probably not 
worth mentioning ;-) 

> 
> 
> >
> >Small observation for 4.3:  enabling the send-refresh option is a
> >dangerous thing. It's not only they may keep up active entries in the
> >fast-path forever (since there is always some traffic generated by the
> >'probes'), it's also that the IP/MAC binding 'kept up' even if there is
> >no traffic is sitting in all PEs as RT-2.  The section talks about
> >advantages, maybe it deserves a sentence to point out the dangers of
> >such behavior.
> 
> [JORGE] send-fresh is optional and should be enabled/disabled depending on the
> use-case. The purpose is in fact keep local IP->MAC bindings active and make
> sure they are still valid before withdrawing the RT2s. It can also help 
> keeping
> active not only the proxy entry but also the MAC-VRF entry. If the user wants 
> to
> rely purely on the age-time, that should be allowed. Not sure why this is a
> danger?

 [Tony saiz:]  because disabling aging will basically accumulate more and more 
state in fwd path even if the src/dst pairs don't talk to each other anymore. 
In your customer's scenario that's what's needed, in e.g. sparse, large scale 
EVPN deployments in backbone it's probably not what a carrier would be excited 
about given PE state is expensive.

> >
> >[Tony saiz:]   as I wrote in other email, the problem is if the first
> >route goes, the second should be honored IMO. It seems to me we have
> >this very case BTW with the aliased default gateways?
> 
> [JORGE] Yes, if the first route is withdrawn (IP1->M1), the second
> (IP1->M2) will be now installed in the proxy-arp/nd table. As long as the BGP
> route is kept we are good. A different thing is anycast, in which case
> IP1->M1 and IP1->M2 are both valid at the same time. We will tackle this
> in the next rev.
> 

 [Tony saiz:]  I agree with that (i.e. the 2nd best BGP route is GARP'ed).  The 
anycast in ipv4 is a rare animal from the sightings I had so I'm only concered 
about the 'aliased default GW' case I guess. 

> >
> >> >>
> >> >> d)eVPN draft does not explain anything about possibility to snoop
> >> >> @ DHCP
> >>
> >> [JORGE] do you mean in the proxy-arp/nd draft or in the base spec?
> >> In the proxy-arp/nd only ARP/ND messages are used. DHCP is not always
> >>there.
> >> Not there in the IXP use-case anyway.
> >
> > [Tony saiz:]  agreed,  I just read the draft in wider scope than just
> >IXP and that's why I'm asking.
> 
> [JORGE] IMHO focusing on learning arp/nd for the time being is simpler, and 
> it is
> really what we want to keep under control to reduce flooding.
> But we can discuss.

 [Tony saiz:]  agreed. Maybe one sentence placeholder like "DHCP and other 
strange fruit can be snooped beside to learn the IP/MAC bindings" ;-) 


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