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@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@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@ipng.ch>
PBVP1-RIPE https://ipng.ch/