Cumulus EVPN-VXLAN Lab — Built Fast with Containerlab

After rebuilding my Arista SR-MPLS lab on Containerlab, I wanted to keep that same workflow and move into Cumulus EVPN-VXLAN. This time the goal was not just to recreate a fabric, but to get hands-on quickly with a repeatable topology, fast verification, and a workflow that fits naturally with automation and AI. Why I built this lab My earlier Containerlab work focused on Arista SR-MPLS. That exercise proved something important: once the topology, startup configs, and validation flow are written as code, the time from idea to working lab drops dramatically. ...

May 15, 2026 · 6 min

DHCP Relay in EVPN-VXLAN

In previous posts, I discussed the construction of an EVPN-VXLAN fabric using Cisco NDFC. A critical aspect often overlooked — and the focus of this post — is the transition from a traditional 3-tier data centre architecture to an EVPN-VXLAN setup. One notable challenge in this transition is the configuration of the DHCP relay. Why DHCP Relay Behaves Differently in EVPN-VXLAN Traditionally, DHCP relays are configured to identify the default gateway using link-selection (DHCP Option 82 sub-option 5), ensuring IP addresses are allocated from the correct scope. ...

December 1, 2023 · 4 min · Gary Wong