Leaf spine fabrics?
Data centres, VMs, core distribution access model (legacy), clos networks, leaf spine model. Superspine. Collapsed spine.
Hands on: Quick look at the lab architecture.
The underlay network
Data centre challenges, L2, L3, comparison of STP, OSPF, IS-IS and BGP in DC fabrics. Loopbacks, ECMP.
Hands on: Base network IP fabric (OSPF for didactic reasons), test ECMP paths.
What is VXLAN?
RFC 7348, VLANs, VXLAN, the need for network overlays, tunnelling, tunnel encapsulation, the VXLAN protocol stack, MAC in UDP, the VXLAN header, inner/outer headers.
Hands on: Simple VXLAN configuration, inspecting encapsulated frames and VXLAN headers.
VXLAN architecture
Edge devices, VTEP, VNI. Static VLAN to VNI mapping. Ingress/egress processing, L2 bridging across overlay.
Hands on: Analysing the underlay overlay relationship and packet walkthroughs. VXLAN troubleshooting indicators.
Why EVPN?
VXLAN flood and learn limitations, BUM traffic, unicast BUM, multicast BUM, scalability issues.
Hands on: (For comparison—not recommended in production) BUM traffic analysis. Flooded ARP.
What is EVPN?
Control and data planes. Control plane: Learning, route distribution, peer discovery. RFC 7432, MP-BGP. Data plane, VXLAN and others.
Hands on: BGP EVPN session configuration and verification.
MP-BGP VPN terminology
VPN address family, VRFs, RD/RT. Tenant segmentation. Multi-VRF and Route Target Usage. VRFs, RD/RT.
Hands on: Configure multiple VRFs; verify isolation between tenants. EVPN tables.
BGP EVPN Route Types
AFI/SAFI for EVPN. EVPN route types 1-5, MAC/IP advertisements, Multihoming with Ethernet Service Identifiers (ESI) and Designated Forwarders (DF).
Hands on: Verify RT-2 routes in control plane. Wireshark: Decode EVPN updates.
EVPN overlay peering
iBGP vs eBGP. iBGP full mesh or route reflectors. eBGP with unique ASN per VTEP. AS_PATH behaviour, vendor-specific differences.
Hands on: Convert EVPN peering from iBGP to eBGP; observe route changes. Walkthrough: Examine control-plane updates and ASNs
EVPN-VXLAN integration
Core VTEP roles. Bridged Overlay. EVPN-driven MAC learning, VNI advertisements.
Hands on: Remove static VNI mapping; confirm control-plane learning. Packet Walkthrough: EVPN-based MAC/IP flow with show verification
Inter VNI traffic
VXLAN bridging, Routed overlay. CRB. Edge routed bridging. IRB interfaces. Anycast gateways. Symmetric routing. Proxy ARP and ARP suppression. CRB vs ERB.
Hands on: Adding IRB to VTEPs, Inter VNI traffic with anycast gateways. ARP suppression.
VXLAN DCI
Data Centre Interconnect. VNIs across DCs.
Recap and design considerations
Underlay/overlay paths. EVPN versus flood and learn. Design trade offs: CRB vs ERB, HER vs multicast, static vs control plane.
