evpn rebase to HEAD

[Pim van Pelt]

Hoi,

On 11.03.2026 08:41, Ondrej Zajicek wrote:
> I think it is because you have the same route distinguisher 8298:200 
> on all these routers. If i understand it correctly, each router should 
> use different RD (while they use the same route target (RT) if they 
> are in the same VPN).
I interpreted RFC 7432, Section 7.9 differently
"An RD MUST be assigned for a given MAC-VRF on a PE. *This RD MUST be 
unique across all MAC-VRFs on a PE*. It is RECOMMENDED to use the Type 1 
RD [RFC4364]. The value field comprises an IP address of the PE 
(typically, the loopback address) followed by a number unique to the PE."

(emphasis mine) While the RFC mandates uniqueness only within a single 
PE (across its MAC-VRFs), it als recommends Type 1 RDs using the PE's 
loopback IP, which happens to produce globally unique RDs across the 
network.

I was further thrown off because on a set of Nokia SR-Linux routers that 
run an eVPN VxLAN mesh, the RDs are indeed the same:
A:pim at asw120# info flat / network-instance peeringlan protocols bgp-vpn 
bgp-instance 1
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-distinguisher rd 65500:2604
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-target export-rt target:65500:2604
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-target import-rt target:65500:2604

A:pim at asw100# info flat / network-instance peeringlan protocols bgp-vpn 
bgp-instance 1
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-distinguisher rd 65500:2604
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-target export-rt target:65500:2604
set / network-instance peeringlan protocols bgp-vpn bgp-instance 1 
route-target import-rt target:65500:2604
which is why I would've assumed adding multiple Bird2's with RD 
65500:2604 would be the idiomatic way to do this.

However the important bits are that (a) I can now rely on etab having 
the multiple IMETs as you said, so I can simplify my vppevpn protocol to 
rely only on etab, and not evpntab; and (b) I learned a lot :) Thank you 
so much!

groet,
Pim
-- 
Pim van Pelt <pim at ipng.ch>
PBVP1-RIPE https://ipng.ch/
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