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    EVPN-VXLAN explained: how it works and when you actually need it

    TechLeague Editorial··8 min read

    EVPN-VXLAN is the standard fabric for modern data centers and many campuses. The architecture is simple — the operations are not.

    Topology

    • Spine-leaf with no STP between leafs.
    • Underlay with eBGP unnumbered or OSPF/IS-IS.

    Control plane

    • BGP EVPN distributes MAC and IP reachability.
    • Route Targets for tenancy.

    Data plane

    • VXLAN encapsulation; VTEPs are the leaves.
    • MTU planning critical (jumbo).

    Gateway

    • Anycast gateway on every leaf — same IP/MAC.
    • Symmetric IRB for inter-VLAN routing.

    Vendors

    • Cisco NX-OS, Arista EOS, Aruba CX, Juniper Junos all interoperate.

    Train fabric reasoning in a TechLeague tournament.