VxLAN and vPC Anycast VTEP
Problem with VXLAN and vPC:
- in a vPC both vPC peers duplicate EVPN MAC/IP routes to spine RRs
- with other attributes equal, one vPC peer is always preferred for dual attached hosts (based on the normal BGP Best path selection)
Result: egress traffic from vPC Member is load-balanced, but return ingress traffic is polarized
Solution: Anycast VTEP address - Loopback 0 ip address secondary, the same on both vPC peers:
conf t
interface Loopbak 0_
ip address 1.1.1.111/32 secondaryBGP automatically sets the next-hop to the secondary IP address.
From the Spines (NXOS1 and NXOS2) and another leaf (NXOS7)
