This topic is to discuss the following lesson:
Can you explain this but using 2 or more spine switches?
Hello Dimas
The configuration doesn’t change much if you add more spine switches. The Leaf switch configurations remain the same. If you have two or more spine switches, you simply have to ensure that you have configured EVPN as the overlay, and that you have configured BGP using the L2VPN EVPN address family. As long as BGP has converged, your network will function.
This is an excellent exercise that you can try out in an emulator. It will definitely help you to gain a deeper understanding of the intricacies involved in VXLAN MP-BGP EVPN configurations. If you do so, let us know how you get along!
I hope this has been helpful!
Laz
You can also use this topology:
I’m breaking down the different VXLAN topics into separate examples. If we only need one spine switch to explain a topic, I’ll use one. We’ll add more complex topologies where we combine different topics later.
Rene
Sholdn’t be member vni 10020 under nve on Leaf2 config? 10010 is written.
Hello Funda
You are correct. Under the final configurations for each device, the member vni command should show a value of 10020 and not 10010 as is indicated. The values are correct in the lesson, but not inthe final config. I will let Rene know to make the correction.
Thanks for pointing that out!
Laz
1 Like
How would you recommend building a WAN to interconnect multiple fabrics ,strictly l3vni, that span across different physical datacenters
Hello Nicolas
There are various ways to implement such a topology, and which you will choose will depend upon many additional factors. You do mention however that you want to use Layer 3 communication across multiple VNIs, so you are talking about a VXLAN topology.
Note that VXLAN is typically used within datacenters and cloud infrastructure which typically have very high speed and highly reliable communication paths. If you want to span VXLAN across WAN links, those WAN links should be high throughput robust links too. For this reason, using MPLS or SD-WAN with a reliable physical infrastructure is a good approach. If you would like something more specific, can you share with us more details about the topology and purpose of your network? That will help to zero in on technologies that will suit your requirements.
I hope this has been helpful!
Laz
HI Laz,
Thanks for the input. Any reason why you would run VXLAN over MPLS as opposed to doing something like evpn multsite with point-to-point links that connect border gateways leveraging some type of full-mesh eBGP? In a particular cisco white paper they mentioned using a route server. https://www.cisco.com/c/en/us/products/collateral/switches/nexus-9000-series-switches/white-paper-c11-739942.html
Notice below I have two Leaf Border GWs that are connected to the spines and between border gateways. We want to run VXLAN so that layer 3 communication between each respective VLAN in each DC can take place
I’ve read a few articles about evpn multisite but it seems the recommendation is to only go with that approach when you have 2 DCs , not 3 or anything more…
Hello Nicolas
Your questions require a little bit more insight than just responding to them in a forum post, so I created a NetworkLessons note on the topic of choosing a technology for a multi-datacenter topology.
Concerning your particular diagram, which includes border gateways between the DCs, the VXLAN over MPLS approach with route servers would probably work efficiently for this setup. This ensures that the Layer 3 connectivity across VLANs between all DCs is handled cleanly without introducing additional EVPN MS complexity, especially with the higher number of DCs.
On the contrary, EVPN multisite could become challenging as you expand to three or more data centers.
I hope this and the NetworkLessons note have been helpful for you!
Laz