Mandatory configuration for VxLAN-EVPN

[mhiyoshi]

Dear all,

Currently I am verifying for BGP/EVPN configuration on VxLAN-EVPN.
If I check below manual then basically address-family ipv4 unicast is mandatory configuration
however if it is not configures, then I think it can be functioning as l2VPN EVPN right?
For example, if you can issue "show bgp l2vpn evpn summary" then you can see the peer status.

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/7-x/vxlan/configuration/guide/b_Cisco_Nexus_9000_Series_NX-OS_VXLAN_Configuration_Guide_7x/b_Cisco_Nexus_9000_Series_NX-OS_VXLAN_Configuration_Guide_7x_chapter_0100.html

Configuring BGP on the VTEP

Step 4 - address-family ipv4 unicast - address family for IPv4.
Step 5 - address-family l2vpn evpn - address family Layer 2 VPN EVPN under the BGP neighbor.

Best Regards,

Masanobu Hiyoshi

[ray.deasy]

So under the tenant VRF you have to redistribute/advertise the locally connected routes, If you do not do this under the ipv4 unicast address family (within the vrf) the type 5 prefix routes will not be advertised,

Your type 2 routes will show up but not your type 5 routes - show bgp l2vpn evpn

example:

This is a leaf VTEP Config: 

router bgp 1
  router-id 9.9.99.4
  template peer IBGP_VXLAN
    remote-as 1
    log-neighbor-changes
    update-source loopback0
    address-family l2vpn evpn
      send-community
      send-community extended
  neighbor 9.9.9.5
    inherit peer IBGP_VXLAN
  neighbor 9.9.9.6
    inherit peer IBGP_VXLAN
  vrf EVPN-TENANT1
    address-family ipv4 unicast
      redistribute direct route-map CONNECTED
  vrf EVPN-TENANT2
    address-family ipv4 unicast
      redistribute direct route-map CONNECTED
evpn
  vni 11000 l2
    rd auto
    route-target import auto
    route-target export auto
  vni 20000 l2
    rd auto
    route-target import auto
    route-target export auto
vrf context EVPN-TENANT1
  rd auto
  address-family ipv4 unicast
    route-target both auto evpn
vrf context EVPN-TENANT2
  rd auto
  address-family ipv4 unicast
    route-target both auto evpn

!Now if I remove the redistribution under the ipv4 unicast address family you will see the type 5 routes disappear as below on this leaf VTEP switch.
ST1-SRV06-LF4# conf t
ST1-SRV06-LF4(config)# router bgp 1
ST1-SRV06-LF4(config-router)#   vrf EVPN-TENANT1
ST1-SRV06-LF4(config-router-vrf)#    address-family ipv4 unicast
ST1-SRV06-LF4(config-router-vrf-af)# no redistribute direct route-map CONNECTED

On this VTEP we now see it as deleted.

 show bgp l2vpn evpn vni 100000
BGP routing table information for VRF default, address family L2VPN EVPN
BGP table version is 29, Local Router ID is 9.9.99.4
Status: s-suppressed, x-deleted, S-stale, d-dampened, h-history, *-valid, >-best
Path type: i-internal, e-external, c-confed, l-local, a-aggregate, r-redist, I-injected
Origin codes: i - IGP, e - EGP, ? - incomplete, | - multipath, & - backup, 2 - best2

   Network            Next Hop            Metric     LocPrf     Weight Path
Route Distinguisher: 9.9.99.4:3    (L3VNI 100000)
* i[5]:[0]:[0]:[24]:[10.1.1.0]/224
                      9.9.99.3                 0        100          0 ?
*>i                   9.9.99.1                 0        100          0 ?
*>i[5]:[0]:[0]:[24]:[10.1.2.0]/224
                      9.9.99.2                 0        100          0 ?
x l                   9.9.99.4                 0        100      32768 ?

On another leaf(ST1-SRV05-LF3#) below we see the type 5 route is missing (sourced )from that leaf 9.9.99.4 - its now only showing as sourced from VTEP  9.9.99.2  as below:

ST1-SRV05-LF3# show bgp l2vpn evpn vni 100000
BGP routing table information for VRF default, address family L2VPN EVPN
BGP table version is 27, Local Router ID is 9.9.99.3
Status: s-suppressed, x-deleted, S-stale, d-dampened, h-history, *-valid, >-best
Path type: i-internal, e-external, c-confed, l-local, a-aggregate, r-redist, I-injected
Origin codes: i - IGP, e - EGP, ? - incomplete, | - multipath, & - backup, 2 - best2

   Network            Next Hop            Metric     LocPrf     Weight Path
Route Distinguisher: 9.9.99.3:3    (L3VNI 100000)
* i[5]:[0]:[0]:[24]:[10.1.1.0]/224
                      9.9.99.1                 0        100          0 ?
*>l                   9.9.99.3                 0        100      32768 ?
*>i[5]:[0]:[0]:[24]:[10.1.2.0]/224
                      9.9.99.2                 0        100          0 ?

ST1-SRV05-LF3# 

Ray.