Configure Next Hop Recursion

You can enable next hop recursion (NHR) on each tenant VRF when you create or update a tenant VRF on the switches.

Before you begin

  • By default, the NHR is disabled.
  • When you upgrade to XCO 3.2.1 or later, the NHR gets disabled on VRF.
  • SLXOS 20.5.1 and later supports the next hop recursion configuration on tenant VRF. For details on hardware support, refer to the SLX-OS documentation.

About this task

Follow this procedure to configure next hop recursion.

Based on the endpoints present in the EPG, VRF is instantiated on the switches when you create an L3 endpoint group or transition an endpoint group to L3 endpoint group. Based on the endpoints present in the EPG, VRF is updated on the switches when you update a VRF.

The next hop recursion is configured when you configure a VRF.

Procedure

  1. Run the following command to enable next hop recursion (NHR) when you create a tenant VRF: 
    efa tenant vrf create --name <vrf-name> --tenant <tenant-name> --next-hop-recursion-enable {true|false}
  2. Run the following command to enable next hop recursion when you update a tenant VRF: 
    efa tenant vrf update --name <vrf-name> --tenant <tenant-name> 
            --operation next-hop-recursion-update –next-hop-recursion-enable {true|false}

Example

efa tenant vrf create --name vs --tenant t1 --next-hop-recursion-enable true
./efa tenant vrf show --tenant t1 --name vs --detail
Name                        : vs
Tenant                      : t1
Routing Type                : distributed
Centralized Routers         : 
Enable Layer3 Extension     : true
Redistribute                : connected
Max Path                    : 8
Local Asn                   : 
L3VNI                       : 
EVPN IRB BD                 : 
EVPN IRB VE                 : 
BR VNI                      : 
BR BD                       : 
BR VE                       : 
RH Max Path                 : 
Enable RH ECMP              : false
Enable Graceful Restart     : false
Enable NextHop Recursion    : true
Route Target                : 
Static Route                :
Static Route BFD            :
Network Route Address       :
Static Network              :
Aggregate Address           :
VRF Type                    : private
State                       : vrf-created
Dev State                   : not-provisioned
App State                   : cfg-ready





efa tenant epg create --name epg1 --tenant t1 --switchport-mode trunk --po po1  --port 10.20.246.15[0/18] --vrf vs --l3-vni 30211 --ctag-range 23-25 --anycast-ip 23:23.10.12.2/24  --anycast-ip 24:24.10.12.1/24 --anycast-ip 25:25.10.12.1/24  --suppress-arp 25:true

efa tenant vrf show --tenant t1 --name vs --detail
Name                        : vs
Tenant                      : t1
Routing Type                : distributed
Centralized Routers         : 
Enable Layer3 Extension     : true
Redistribute                : connected
Max Path                    : 8
Local Asn                   : 
L3VNI                       : 30211
EVPN IRB BD                 : 4096
EVPN IRB VE                 : 8192
BR VNI                      : 
BR BD                       : 
BR VE                       : 
RH Max Path                 : 
Enable RH ECMP              : false
Enable Graceful Restart     : false
Enable NextHop Recursion    : true
Route Target                : import 101:101
                            : export 101:101
Static Route                :
Static Route BFD            :
Static Network              :
Aggregate Address           :
VRF Type                    : private
State                       : vrf-device-created
Dev State                   : provisioned
App State                   : cfg-in-sync


Rack1-Device1# show run router bgp
router bgp
 local-as 4200000000
 capability as4-enable
 fast-external-fallover
 neighbor 10.20.20.3 remote-as 4200000000
 neighbor 10.20.20.3 next-hop-self
 address-family ipv4 unicast
  network 172.31.254.206/32
  network 172.31.254.222/32
  maximum-paths 8
  graceful-restart
 !
 address-family ipv4 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family ipv6 unicast
 !
 address-family ipv6 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family l2vpn evpn
  graceful-restart
 !
!
Rack1-Device1#
 
Rack1-Device2# show run router bgp
router bgp
 local-as 4200000000
 capability as4-enable
 fast-external-fallover
 neighbor 10.20.20.2 remote-as 4200000000
 neighbor 10.20.20.2 next-hop-self
 address-family ipv4 unicast
  network 172.31.254.182/32
  network 172.31.254.222/32
  maximum-paths 8
  graceful-restart
 !
 address-family ipv4 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family ipv6 unicast
 !
 address-family ipv6 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family l2vpn evpn
  graceful-restart
 !
!
Rack1-Device2#
 

efa tenant vrf update --name vs --tenant t1 --operation next-hop-recursion-update --next-hop-recursion-enable false


efa tenant vrf show --tenant t1 --name vs --detail
Name                        : vs
Tenant                      : t1
Routing Type                : distributed
Centralized Routers         : 
Enable Layer3 Extension     : true
Redistribute                : connected
Max Path                    : 8
Local Asn                   : 
L3VNI                       : 30211
EVPN IRB BD                 : 4096
EVPN IRB VE                 : 8192
BR VNI                      : 
BR BD                       : 
BR VE                       : 
RH Max Path                 : 
Enable RH ECMP              : false
Enable Graceful Restart     : false
Enable NextHop Recursion    : false
Route Target                : import 101:101
                            : export 101:101
Static Route                :
Static Route BFD            :
Network Route Address       :
Static Network              :
Aggregate Address           :
VRF Type                    : private
State                       : vrf-device-created
Dev State                   : provisioned
App State                   : cfg-in-sync
Rack1-Device1# show run router bgp
router bgp
 local-as 4200000000
 capability as4-enable
 fast-external-fallover
 neighbor 10.20.20.3 remote-as 4200000000
 neighbor 10.20.20.3 next-hop-self
 address-family ipv4 unicast
  network 172.31.254.206/32
  network 172.31.254.222/32
  maximum-paths 8
  graceful-restart
 !
 address-family ipv4 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family ipv6 unicast
 !
 address-family ipv6 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family l2vpn evpn
  graceful-restart
 !
!
Rack1-Device1#
 
Rack1-Device2# show run router bgp
router bgp
 local-as 4200000000
 capability as4-enable
 fast-external-fallover
 neighbor 10.20.20.2 remote-as 4200000000
 neighbor 10.20.20.2 next-hop-self
 address-family ipv4 unicast
  network 172.31.254.182/32
  network 172.31.254.222/32
  maximum-paths 8
  graceful-restart
 !
 address-family ipv4 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family ipv6 unicast
 !
 address-family ipv6 unicast vrf vs
  next-hop-recursion
  redistribute connected
  maximum-paths 8
 !
 address-family l2vpn evpn
  graceful-restart
 !
!
Rack1-Device2#
9038968-00 Rev AB