BGP peering with external DCI must configure with fabric-external peering for next-hop rewrites in multisite. It is recommended to use the fabric-external command for multisite deployment. Route-target configuration commands for L2 VNI and L3 VNI is configured under address-family L2VPN EVPN. BL in multisite must import external VTEP using manual RT configuration. Auto-RT is enabled by default, but can be come inactive if a user configures manual RT auto-RT. The following table describes these commands, followed by a complete list of commands required at relevant switches.
peer-group external remote-as external capability extended-nexthop ! address-family ipv4 unicast activate ! address-family l2vpn evpn activate fabric-external | Peer with external fabric neighbor Advertise underlay networks with external neighbor Advertise evpn routes with external peer |
address-family l2vpn evpn advertise-all-vni ! vni 10101 route-target both auto route-target import 20101:101 route-target export 10101:101
| Specify L2 VNI route-targets The VNI mapping is not symmetric, use auto rt for internal and manual RT for external to exchange routes RT for importing routes from external fabric i.e., Fabric-B-DC2 RT for exporting the local routes to external fabric i.e., Fabric-B-DC2 Make sure these numbers are unique per VNI |
router bgp 65012 vrf VrfTenant1 router-id 10.0.1.12 | Configure BGP router for Tenant |
address-family ipv4 unicast redistribute connected | Advertise underlay networks and VTEPs |
address-family l2vpn evpn advertise ipv4 unicast default-originate ipv4 rd 65012:1 route-target both auto route-target import 203101:1 route-target export 103101:1 | Advertise all VNIs on overlay for Tenant Advertise default route to internal fabric Specify L3 route-targets RD should be unique per tenant/vrf Auto rt for route exchange btw internal vteps Manual rt for route exchange with downstream fabric i.e., Fabric-B-DC2 |
configure terminal
interface Ethernet44 description "Connected to Fabric B BL1" ipv6 enable no shutdown exit router bgp 65012 address-family l2vpn evpn advertise-all-vni ! vni 10101 route-target both auto route-target import 20101:101 route-target export 10101:101 exit vni 10201 route-target both auto route-target import 20201:201 route-target export 10201:201 exit exit peer-group external remote-as external capability extended-nexthop ! address-family ipv4 unicast activate ! address-family l2vpn evpn activate fabric-external neighbor interface Ethernet44 description "DCI Multisite Neighbor" peer-group external end |
configure terminal router bgp 65001 vrf VrfTenant1 router-id 10.0.1.1 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast exit exit ! router bgp 65001 vrf VrfTenant2 router-id 10.0.1.1 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast exit exit end write memory | configure terminal router bgp 65012 vrf VrfTenant1 router-id 10.0.1.12 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast default-originate ipv4 rd 65012:1 route-target both auto route-target import 203101:1 route-target export 103101:1 exit exit ! router bgp 65012 vrf VrfTenant2 router-id 10.0.1.12 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast default-originate ipv4 rd 65012:2 route-target both auto route-target import 203102:1 route-target export 103102:1 end write memory |
configure terminal
interface Ethernet92 description "Connected to Fabric B BL1" ipv6 enable no shutdown exit router bgp 64612 address-family l2vpn evpn advertise-all-vni ! vni 20101 route-target both auto route-target import 10101:101 route-target export 20101:101 exit ! vni 20201 route-target both auto route-target import 10201:201 route-target export 20201:201 exit exit peer-group external remote-as external capability extended-nexthop ! address-family ipv4 unicast activate ! address-family l2vpn evpn activate fabric-external neighbor interface Ethernet92 description "DCI Multisite Neighbor" peer-group external end write memory |
configure terminal
router bgp 64601 vrf VrfTenant1 router-id 10.0.2.1 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast exit exit ! router bgp 64601 vrf VrfTenant2 router-id 10.0.2.11 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast exit exit end write memory | configure terminal
router bgp 64612 vrf VrfTenant1 router-id 10.0.2.12 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast default-originate ipv4 rd 64612:1 route-target both auto route-target import 103101:1 route-target export 203101:1 exit exit ! router bgp 64612 vrf VrfTenant2 router-id 10.0.2.12 ! address-family ipv4 unicast redistribute connected maximum-paths 128 ! address-family l2vpn evpn advertise ipv4 unicast default-originate ipv4 rd 64612:2 route-target both auto route-target import 103102:1 route-target export 203102:1 exit exit end write memory |