Campus Fabric Architecture-Fabric 1; Traffic Flow Between Fabrics-Campus Fabric Interconnect - Cisco Nexus 7000 Series Configuration Manual

Campus Fabric Interconnect - MPLS L3VPN
Fabric 1 and Fabric 2 are two campus fabrics. PxTR 1 and PxTR 2 are Cisco Nexus 7000/7700 Series switches
that perform the role of border switches in Fabric 1. PxTR 2 is the fabric border switch in Fabric 2. MPLS
configurations are enabled on the PxTR switches such that Fabric 1 and Fabric 2 are connected through MPLS
L3VPN between PxTR 1/PxTR 2 and PxTR 3.
Campus Fabric Architecture—Fabric 1
End hosts are attached to Cisco Catalyst switches xTR 1 and xTR 2 which perform the role of LISP xTRs.
The LISP control plane extends from the xTRs to PxTR 1 and PxTR 2. Spine1 and Spine 2 are Layer-3
switches used for routing in the underlay, through an interior gateway protocol (IGP) such as Open Shortest
Path First (OSPF). Spine 1 is connected to the Map-Server/Map-Resolver (MSMR).
For the overlay, VXLAN is implemented on the xTRs and the PxTRs, and they also perform the role of
VXLAN Virtual Tunnel End Points (VTEPs).
The LISP (control plane) and the VXLAN (data plane) overlays begin and terminate between the xTRs and
PxTRs.
Traffic Flow Between Fabrics—Campus Fabric Interconnect
PxTR1 and PxTR2 perform the provider edge (PE) function, and are connected to the provider switch P1 in
the MPLS/IP core. MPLS L3VPN is implemented on the PxTRs for traffic flow across the fabrics. If Host 1
in Fabric 1 sends traffic to Host 3 in Fabric 2, then this is a sample flow:
• Traffic from Host1 reaches a PxTR, the fabric border switch, since the destination end host is located
• P1 sends the traffic through the MPLS/IP core to the Provider switch P2 which is connected to the fabric
• PxTR3 receives the traffic, removes the MPLS label, and does appropriate lookups as regards to the
• xTR 3 receives the traffic, VXLAN decapsulates the packets and sends the original packets (sent by
in a remote site. The PxTR VXLAN decapsulates the packets and sends it towards P1 through MPLS.
The redistribute lisp route-map command ensures that the LISP map-cache routes are
Note
redistributed into Multiprotocol Border Gateway Protocol (MP-BGP).
border switch of Fabric 2, PxTR 3. P2 forwards the MPLS traffic to PxTR3.
Note The assumption is that MPLS L3VPN is implemented on the receiving switch and the
LISP control plane and VXLAN data planes are converged/updated.
destination end host. Then, PxTR3 VXLAN encapsulates the packets towards xTR3, since Host 3 is
attached to it.
Host 1) to Host 3.
Campus Fabric Architecture—Fabric 1
Cisco Nexus 7000 Series NX-OS VXLAN Configuration Guide
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