Ethernet VPN (EVPN)
ChatGPT trying (and failing) to explain EVPN
What Is EVPN?
Before going into the technical details, let’s start with the basics: What is EVPN, how does it work, and where can you use it?
- What Is EVPN?
- EVPN: The Great Unifying Theory of VPN Control Planes?
- EVPN Is More than VPLS on Steroids
- BGP, EVPN, VXLAN, or SRv6?
- Multivendor EVPN Just Works
- Why Are We Using EVPN Instead of SPB or TRILL?
- VXLAN Broadcast Domain Size Limitations
- Active-Active Data Centers with VXLAN and EVPN
- Comparing EVPN with Flood-and-Learn Fabrics
- Studying EVPN to Prepare for a Job Interview
- Is Dynamic MAC Learning Better Than EVPN?
- Dataplane MAC Learning with EVPN
EVPN Designs
EVPN was designed to be used in an IBGP environment on top of an IGP. With the eruption of EBGP as better IGP hype, many vendors tried to adapt EVPN to an environment running EBGP instead of OSPF. We covered some of the typical EVPN designs in these blog posts:
- BGP in EVPN-Based Data Center Fabrics
- Using EVPN in Very Small Data Center Fabrics
- Pragmatic EVPN Designs
- VXLAN Leaf-and-Spine Fabric
- IBGP Full Mesh Between Leaf Switches
- BGP Route Reflectors Considered Harmful
- Scaling IBGP with Route Reflectors
- EBGP Everywhere
- EVPN EBGP over IPv4 EBGP
- EVPN IBGP over IPv4 EBGP
Other blog posts focus on various design details:
- BGP in EVPN-Based Data Center Fabrics (Updated)
- Scaling EVPN BGP Routing Designs
- Implications of Valley-Free Routing in Data Center Fabrics
- VXLAN and EVPN on Hypervisor Hosts
- When EVPN EBGP Session between Loopbacks Makes Sense
- BGP AS Numbers on MLAG Members
- EVPN/VXLAN or Bridged Data Center Fabric?
- Multi-Vendor EVPN Fabrics
- Layer-3 WAN Handoff (L3Out) in VXLAN/EVPN Fabrics
- VXLAN/EVPN Layer-3 Handoff (L3Out) on Arista EOS
Finally, several blog posts describe various EVPN VPN topologies:
- Simple EVPN/VXLAN Bridging
- Building Layer-3-Only EVPN Lab
- Layer-3-Only EVPN: Behind the Scenes
- Common Services VRF with EVPN Control Plane
- Hub-and-Spoke VPN Topology
- EVPN Hub-and-Spoke Layer-3 VPN
EVPN Implementation Details
There are tons of tiny little things that can go wrong when you try to deploy EVPN. I documented them as I stumbled upon them:
- EVPN Route Target Considerations in EBGP Environment
- Using 4-Byte BGP AS Numbers With EVPN on Junos
- Dissecting IBGP+EBGP Junos Configuration
- Private VLANs With VXLAN
- VMware NSX Killed My EVPN Fabric
- EVPN Route Targets, Route Distinguishers, and VXLAN Network IDs
- EVPN Auto-Rd and Duplicate MAC Addresses
- Next-Hop and VTEP Reachability in EVPN Networks
- Duplicate ARP Replies with Anycast Gateways
- More Arista EOS BGP Route Reflector Woes
- Using EVPN/VXLAN with MLAG Clusters
- DHCP Relaying in EVPN VRFs
- Silent Hosts in EVPN Fabrics
- Repost: Campus-Wide Wireless Roaming with EVPN
- Using Multiple Transit VNIs per EVPN VRF
Beyond VXLAN
While EVPN is often used with VXLAN today, it was designed to work with the MPLS data plane, resulting in a few quirks:
- EVPN With MPLS Data Plane in Data Centers
- Q-in-Q Support in Multi-Site EVPN
- EVPN/MPLS Bridging Forwarding Model
- EVPN VLAN-Aware Bundle Service
- Does EVPN/VXLAN over SD-WAN Make Sense?
- Per-Prefix and Per-VRF MPLS/VPN and EVPN Labels/VNIs
EVPN Rants
Some vendors’ marketing engineers (or Senior Directors) can’t stand anyone telling them their implementation might be suboptimal, going to great lengths to prove to themselves they’re right, and generating beautiful fodder for rants.
- Don’t Sugarcoat the Challenges You Have
- The EVPN Dilemma
- The EVPN/EBGP Saga Continues
- EVPN Control Plane in Infrastructure Cloud Networking
- EVPN/VXLAN Complexity
- On the Viability of EVPN
- Multi-Vendor EVPN Fabrics
- LISP vs EVPN: Mobility in Campus Networks
Videos
You can watch numerous videos from the EVPN Technical Deep Dive webinar without an ipSpace.net account:
- EVPN Multihoming Taxonomy and Overview
- EVPN Multihoming Deep Dive
- MLAG with EVPN
- vPC Fabric Peering with EVPN Multihoming
- Advantages and Drawbacks of EVPN-based Multihoming
What Others Wrote About EVPN
- EVPN in Data Center
- Arista EVPN-Based Automation Virtual Lab
- Switching to IP fabrics
- ARP Problems in EVPN
- EVPN/VXLAN with FRR on Linux Hosts
- Troubleshooting EVPN Control Plane
- Introduction of EVPN at DE-CIX