Configure Backup Routing on Tenant VRF

About this task

Enable backup routing when all the links from a leaf device to the spine layer are down, and tenant traffic is to be routed via the MCT neighbor.

IPv4 and IPv6 range are the input at the fabric level. A pair of IPv4 and IPv6 address is allocated to each MCT pair across all the tenant VRFs, and the BGP session is established between the same IP Pair.

Procedure

  1. Allocate a pair of IPv4 and IPv6 address to each MCT pair across all the tenant VRFs.
    1. Allocate a bridge domain per VRF for backup routing.
    2. Allocate a corresponding router-interface VE per BD or VRF.
    3. Assign the IPv4 and IPv6 address allocated to each device on each of the VE interface.
      Note

      Note

      Same IPv4 and IPv6 address is allocated on each of the VE interface which belongs to different VRF.
    4. Establish IBGP IPv4 neighborship with the MCT peer on a set of IP address per VRF.
    5. Establish IBGP IPv6 neighborship with the MCT peer on a set of IPv6 address per VRF.
    6. Configure "next-hop-self" on both the IPv4 and IPv6 neighbor.
    7. Configure "active" on the IPv6 neighbor.

    Example:

    efa fabric setting update --name fabric1
--backup-routing-ipv4-range 21.1.1.0/24 --backup-routing-ipv6-range 2001:21:1:1::0/120

    Example when backup routing is enabled:

    efa fabric setting update --name nc --backup-routing-enable yes
  2. Configure devices on tenant VRFs.
    Table 1. Tenant1 VRF “vrf1” 
    leaf-9250-173# show running-config bridge-domain 3001
bridge-domain 3001 p2mp
 pw-profile default
 router-interface Ve 7001
 bpdu-drop-enable
!

leaf-9250-173# sh run in ve 7001
interface Ve 7001 
 vrf forwarding vrf1
 ip address 21.1.1.10/31
 ipv6 address 2001:21:1:1::10/127
 no shutdown
!
    		 
    leaf-9250-173# show running-config router bgp address-family ipv4 unicast vrf vrf1
router bgp
 address-family ipv4 unicast vrf vrf1
  local-as 4210000001
  redistribute connected
  neighbor 21.1.1.11 remote-as 4210000001
  neighbor 21.1.1.11 next-hop-self
  maximum-paths 2
 !
!

leaf-9250-173# show running-config router bgp address-family ipv6 unicast vrf vrf1
router bgp
 address-family ipv6 unicast vrf vrf1
  redistribute connected
  neighbor 2001:21:1:1::11 next-hop-self
  neighbor 2001:21:1:1::11 remote-as 4210000001
  neighbor 2001:21:1:1::11 activate
  maximum-paths 2
 !
!
    Table 2. Tenant2 VRF “vrf2” 
    leaf-9250-173# show running-config bridge-domain 3002
bridge-domain 3002 p2mp
 pw-profile default
 router-interface Ve 7002
 bpdu-drop-enable
!

leaf-9250-173# sh run in ve 7002
interface Ve 7002 
 vrf forwarding vrf2
 ip address 21.1.1.10/31
 ipv6 address 2001:21:1:1::10/127
 no shutdown
!
    		 
    leaf-9250-173# show running-config router bgp address-family ipv4 unicast vrf vrf2
router bgp
 address-family ipv4 unicast vrf vrf2
  local-as 4210000001
  redistribute connected
  neighbor 21.1.1.11 remote-as 4210000001
  neighbor 21.1.1.11 next-hop-self
  maximum-paths 2
 !
!

leaf-9250-173# show running-config router bgp address-family ipv6 unicast vrf vrf2
router bgp
 address-family ipv6 unicast vrf vrf2
  redistribute connected
  neighbor 2001:21:1:1::11 next-hop-self
  neighbor 2001:21:1:1::11 remote-as 4210000001
  neighbor 2001:21:1:1::11 activate
  maximum-paths 2
 !
!
9037624-00 RevAA