[bess] Re: Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2

["Dikshit, Saumya" <[e-mail]>]

Hello Luc, et All,

I totally understand that rfc7432 forms the core of the EVPN solutions, hence might be something already discussed many a times, long long time ago.
Kindly help with the clarification.

Regards,
Saumya.

From: Dikshit, Saumya <saumya.dikshit=[e-mail]>
Sent: Thursday, December 5, 2024 10:30 PM
To: Dikshit, Saumya <[e-mail]>; Luc André Burdet <[e-mail]>; [e-mail]
Cc: Devarajan, Venkatavaradhan <[e-mail]>
Subject: RE: Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2

Hi Luc,

Kindly help close on my understanding or lack-of-it.

Regards,
Saumya.

From: Dikshit, Saumya <saumya.dikshit=[e-mail]<mailto:saumya.dikshit=[e-mail]>>
Sent: Wednesday, December 4, 2024 9:35 PM
To: Luc André Burdet <[e-mail]<mailto:[e-mail]>>; Dikshit, Saumya <[e-mail]<mailto:[e-mail]>>; [e-mail]<mailto:[e-mail]>
Cc: Devarajan, Venkatavaradhan <[e-mail]<mailto:[e-mail]>>
Subject: RE: Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-14.1.2__;Iw!!NpxR!hgMMC-cnFKkTDh7pK40gEGO9UZWvSoAZB1ZFtCQ595y81yC959lX1ylo8_H0eNBH2ZAutEEYkHBdqxeg8D02hiZH3i8WlXJPDA$>

Hi Luc,

Thanks for your response.
I did considered Aliasing before posting the question.

In the context of my query, are you referring to the following statement in section 8.4.1.
https://datatracker.ietf.org/doc/html/rfc7432#section-8.4.1<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-8.4.1__;Iw!!NpxR!iqfVrFsLnWWJHvsJl3BL46z8SuGxQYZvBYegH2-t9Yyk-wgH7UUnh2QYG-alXHLDPUkd_tZcRZXHGTam6JmWyRFsYj3Ct9m-Dg$>
"This section describes the procedures used to construct the Ethernet
   A-D per EVPN instance (EVI) route, which is used for aliasing (as
   discussed above).  Support of this route is OPTIONAL."


What I infer from "OPTIONAL" is that the "Aliasing" feature is optional
or
it implies that with ONLY "A-D per ESI" route, aliasing can be realized.
And that can be done by trusting the EVI mapping (VNI/Label) published with RT-2 ?
Thought that does not ensures the association of EVI to ESI on the publishing PE.

Regards,
Saumya

From: Luc André Burdet <[e-mail]<mailto:[e-mail]>>
Sent: Wednesday, December 4, 2024 7:51 PM
To: Dikshit, Saumya <saumya.dikshit=[e-mail]<mailto:saumya.dikshit=[e-mail]>>; [e-mail]<mailto:[e-mail]>
Cc: Devarajan, Venkatavaradhan <[e-mail]<mailto:[e-mail]>>
Subject: [bess] Re: Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-14.1.2__;Iw!!NpxR!iqfVrFsLnWWJHvsJl3BL46z8SuGxQYZvBYegH2-t9Yyk-wgH7UUnh2QYG-alXHLDPUkd_tZcRZXHGTam6JmWyRFsYj1wsTlF4w$>

Saumya,

That's not what the section says, please read it together with section 8.4 (aliasing).

Regards,
Luc André

Luc André Burdet |  Cisco  |  [e-mail]<mailto:[e-mail]>  |  Tel: [phone]


From: Dikshit, Saumya <saumya.dikshit=[e-mail]<mailto:saumya.dikshit=[e-mail]>>
Date: Tuesday, December 3, 2024 at 22:06
To: Dikshit, Saumya <saumya.dikshit=[e-mail]<mailto:saumya.dikshit=[e-mail]>>, [e-mail]<mailto:[e-mail]> <[e-mail]<mailto:[e-mail]>>, [e-mail]<mailto:[e-mail]> <[e-mail]<mailto:[e-mail]>>
Cc: Devarajan, Venkatavaradhan <[e-mail]<mailto:[e-mail]>>
Subject: [bess] Re: Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-14.1.2__;Iw!!NpxR!nQ2KLFuPoNiMjeSLwZf4spUyHXL1x_sDI_irSP9X1TflXPXAoCHwSiI21dvlT3HwUGDYayqJxqZ5XyIVxqs7jG3r$>
Any one from the rfc7432 authors, members, and/or chairs, if they can help on below.
A response will surely help establish logic behind behavior observed across vendors.

Regards,
Saumya.

From: Dikshit, Saumya <saumya.dikshit=[e-mail]<mailto:saumya.dikshit=[e-mail]>>
Sent: Tuesday, December 3, 2024 5:52 PM
To: [e-mail]<mailto:[e-mail]>; [e-mail]<mailto:[e-mail]>
Cc: Devarajan, Venkatavaradhan <[e-mail]<mailto:[e-mail]>>
Subject: [bess] Query related to rfc7432, multihoming : https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-14.1.2__;Iw!!NpxR!nQ2KLFuPoNiMjeSLwZf4spUyHXL1x_sDI_irSP9X1TflXPXAoCHwSiI21dvlT3HwUGDYayqJxqZ5XyIVxqs7jG3r$>


Hello All,



I have question in context of multiple path reachability to a MAC route published with an ESI in an RT-2.

Are both "Ethernet A-D per EVI route" and "Ethernet A-D per ES route" mandated to determine/establish reachability via more than one paths to the advertised MAC ?

Or Just "Ethernet A-D per ES route" should suffice to determine the same ? The RFC seems to mandate both for determining more than one path.s



The related excerpts from the rfc7432 https://datatracker.ietf.org/doc/html/rfc7432#section-14.1.2<https://urldefense.com/v3/__https:/datatracker.ietf.org/doc/html/rfc7432*section-14.1.2__;Iw!!NpxR!mMMrO31ZsVA-Ltu3w56iNZRxb9pX92bqk6XiOshUPcitwhZ9LCeGgJKn5bJYYfVpUraEGr-gSaoZ3fx9K1eHungZa5WIuQrEUg$>

"A remote PE that receives a MAC/IP Advertisement

   route with a non-reserved ESI SHOULD consider the advertised MAC

   address to be reachable via all PEs that have advertised reachability

   to that MAC address's EVI/ES via the combination of an Ethernet A-D

   per EVI route for that EVI/ES (and Ethernet tag, if applicable) AND

   an Ethernet A-D per ES route for that ES."


Regards,
Saumya.