Deployment Guide

4. Configure the border-leaf to advertise the default route into the EVPN in each VRF. From the other VTEPs, any traffic to an
external network and also to networks which are not within the local VRF reaches the Border Leaf router using this default
route.
a. If the border-leaf is already getting a default route from an external router for each VRF: Advertise the BGP
route using the advertise ipv4 bgp command for each VRF in the EVPN.
OS10(config)# evpn
OS10(config-evpn)# vrf Yellow
OS10(config-evpn-vrf-Yellow)# advertise ipv4 bgp
OS10(config-evpn-vrf-Yellow)# exit
OS10(config-evpn)# vrf Green
OS10(config-evpn-vrf-Green)# advertise ipv4 bgp
OS10(config-evpn-vrf-Green)# exit
b. If the border-leaf does not get a default route from an external router: Configure a static null default route in each
VRF and advertise it using advertise ipv4 static command for each VRF in the EVPN.
OS10(config)# ip route vrf Yellow 0.0.0.0/0 interface null 0
OS10(config)# ip route vrf Green 0.0.0.0/0 interface null 0
OS10(config)# evpn
OS10(config-evpn)# vrf Yellow
OS10(config-evpn-vrf-Yellow)# advertise ipv4 static
OS10(config-evpn-vrf-Yellow)# exit
OS10(config-evpn)# vrf Green
OS10(config-evpn-vrf-Green)# advertise ipv4 static
OS10(config-evpn-vrf-Green)# exit
5. (Optional) Configure route-maps with a prefix-list to leak selective routes from each VRF.
OS10(config)# ip prefix-list PrefixList_DefaultVrf_Export permit 10.10.0.0/24
OS10(config)# ip prefix-list PrefixList_YellowVrf_Export permit 10.1.0.0/24 le 32
OS10(config)# ip prefix-list PrefixList_GreenVrf_Export permit 10.2.0.0/24
OS10(config)# ip prefix-list PrefixList_RedVrf_Export permit 10.3.0.0/24
OS10(config)# route-map RouteMap_DefaultVrf_Export
OS10(config-route-map)# match ip address prefix-list PrefixList_DefaultVrf_Export
OS10(config-route-map)# exit
OS10(config)# route-map RouteMap_YellowVrf_Export
OS10(config-route-map)# match ip address prefix-list PrefixList_YellowVrf_Export
OS10(config-route-map)# exit
OS10(config)# route-map RouteMap_GreenVrf_Export
OS10(config-route-map)# match ip address prefix-list PrefixList_GreenVrf_Export
OS10(config-route-map)# exit
OS10(config)# route-map RouteMap_RedVrf_Export
OS10(config-route-map)# match ip address prefix-list PrefixList_RedVrf_Export
OS10(config-route-map)# exit
NOTE:
While leaking EVPN routes, only the subnet routes must be leaked. Host routes (/32) need not be leaked and
could be blocked using route-maps. But, if you have certain VNs stretched on the border-leaf as well (like in Yellow
VRF), you must leak the host routes as well.
6. Configure route leaking between:
● Yellow VRF and default VRF.
● Yellow VRF and Green VRF.
● Yellow VRF and Red VRF.
OS10(config)# ip vrf default
OS10(conf-vrf)# ip route-export 0:0 route-map RouteMap_DefaultVrf_Export
OS10(conf-vrf)# ip route-import 1:1
OS10(conf-vrf)# exit
OS10(config)# ip vrf Yellow
OS10(conf-vrf)# ip route-export 1:1 route-map RouteMap_YellowVrf_Export
OS10(conf-vrf)# ip route-import 0:0
OS10(conf-vrf)# ip route-import 2:2
OS10(conf-vrf)# ip route-import 3:3
OS10(conf-vrf)# exit
OS10(config)# ip vrf Green
OS10(conf-vrf)# ip route-export 2:2 route-map RouteMap_GreenVrf_Export
OS10(conf-vrf)# ip route-import 1:1
OS10(conf-vrf)# exit
OS10(config)# ip vrf Red
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VXLAN