[bess] clarification needed on EVPN IP ALIASING draft- kindly enlighten

Praveen Reddy <mpkr43@yahoo.in> Thu, 17 November 2022 07:02 UTC

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Date: Thu, 17 Nov 2022 07:02:08 +0000
From: Praveen Reddy <mpkr43@yahoo.in>
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Subject: [bess] clarification needed on EVPN IP ALIASING draft- kindly enlighten
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Hi, 
It is mentioned in the EVPN IP ALIASING Draft that a synchronised ARP entry  gets created in forwarding on MH node when a MAC/IP is Received fron other MH PE and ESI is locally attached but not needed to re-originate the MAC/IP route advertisement.
copy pasting the snippet mentioned in the drafthttps://datatracker.ietf.org/doc/draft-sajassi-bess-evpn-ip-aliasing/
" In a case where H1 is locally learned only on PE1 due to LAG hashing   or a single routing protocol adjacency to PE1, at PE3, H1 has ECMP   path list (PE1/PE2) using Aliasing as described in this document.   Traffic from H3 can reach H1 via either PE1 or PE2.
   PE2 should install local forwarding state for EVPN IP routes   advertised by other PEs attached to the same ES (i.e., PE1) but not   advertise them as local routes.  When the traffic from H3 reaches   PE2, PE2 will be able forward the traffic to H1 without any   convergence delay (caused by triggering ARP/ND to H1 or to the next-   hop to reach H1).  The synchronization of the EVPN IP routes acrossg   all PEs of the same Ethernet Segment is important to solve   convergence issues."

Below are the few queries I have, Can someone kindly clarify and enlighten me with more details.
Are there any particular reasons why this synchronised route is not required to re-originate ? Do we foresee any problems?
Is re-origination of sync'd MAC/IP route and IP Aliasing implementation is mutually exclusive ?
Thanks for your reply in advance.

Thanks,Praveen