Troubleshooting EVPN Type-2 Route Advertisement

Troubleshooting EVPN Type-2 Route Distribution to a DCIG

For optimal traffic forwarding in an EVPN topology, you can enable fabric spines to distribute host routes to a Data Center Interconnect Gateway (DCIG) using EVPN type-2 (MAC-IP) routes along with the public BD subnets in the form of BGP EVPN type-5 (IP Prefix) routes. This is enabled using the HostLeak object. If you encounter problems with route distribution, use the steps in this topic to troubleshoot.

SUMMARY STEPS

  1. Verify that HostLeak object is enabled under the VRF-AF in question, by entering a command such as the following in the spine-switch CLI:
  2. Verify that the config-MO has been successfully processed by BGP, by entering a command such as the following in the spine-switch CLI:
  3. Verify that the public BD-subnet has been advertised to DCIG as an EVPN type-5 route:
  4. Verify whether the host route advertised to the EVPN peer was an EVPN type-2 MAC-IP route:
  5. Verify that the EVPN peer (a DCIG) received the correct type-2 MAC-IP route and the host route was successfully imported into the given VRF, by entering a command such as the following on the DCIG device (assuming that the DCIG is a Cisco ASR 9000 switch in the example below):

DETAILED STEPS

Step 1

Verify that HostLeak object is enabled under the VRF-AF in question, by entering a command such as the following in the spine-switch CLI:

Example:

spine1# ls /mit/sys/bgp/inst/dom-apple/af-ipv4-ucast/ 
ctrl-l2vpn-evpn  ctrl-vpnv4-ucast  hostleak  summary

Step 2

Verify that the config-MO has been successfully processed by BGP, by entering a command such as the following in the spine-switch CLI:

Example:

spine1# show bgp process vrf apple

Look for output similar to the following:

 Information for address family IPv4 Unicast in VRF apple
    Table Id                   : 0
    Table state                : UP
    Table refcount             : 3
    Peers      Active-peers    Routes     Paths      Networks   Aggregates
    0          0               0          0          0          0         

    Redistribution                
        None

    Wait for IGP convergence is not configured
    GOLF EVPN MAC-IP route is enabled
    EVPN network next-hop 192.41.1.1
    EVPN network route-map map_pfxleakctrl_v4
    Import route-map rtctrlmap-apple-v4
    EVPN import route-map rtctrlmap-evpn-apple-v4

Step 3

Verify that the public BD-subnet has been advertised to DCIG as an EVPN type-5 route:

Example:

spine1# show bgp l2vpn evpn 10.6.0.0 vrf overlay-1
Route Distinguisher: 192.41.1.5:4123    (L3VNI 2097154)
BGP routing table entry for [5]:[0]:[0]:[16]:[10.6.0.0]:[0.0.0.0]/224, version 2088
Paths: (1 available, best #1)
Flags: (0x000002 00000000) on xmit-list, is not in rib/evpn
Multipath: eBGP iBGP

  Advertised path-id 1
  Path type: local 0x4000008c 0x0 ref 1, path is valid, is best path
  AS-Path: NONE, path locally originated
    192.41.1.1 (metric 0) from 0.0.0.0 (192.41.1.5)
      Origin IGP, MED not set, localpref 100, weight 32768
      Received label 2097154
      Community: 1234:444 
      Extcommunity: 
          RT:1234:5101
          4BYTEAS-GENERIC:T:1234:444

  Path-id 1 advertised to peers:
    50.41.50.1

In the Path type entry, ref 1 indicates that one route was sent.

Step 4

Verify whether the host route advertised to the EVPN peer was an EVPN type-2 MAC-IP route:

Example:

spine1# show bgp l2vpn evpn 10.6.41.1 vrf overlay-1
Route Distinguisher: 10.10.41.2:100    (L2VNI 100)
BGP routing table entry for [2]:[0]:[2097154]:[48]:[0200.0000.0002]:[32]:[10.6.41
.1]/272, version 1146
Shared RD: 192.41.1.5:4123    (L3VNI 2097154)
Paths: (1 available, best #1)
Flags: (0x00010a 00000000) on xmit-list, is not in rib/evpn
Multipath: eBGP iBGP

  Advertised path-id 1
  Path type: local 0x4000008c 0x0 ref 0, path is valid, is best path
  AS-Path: NONE, path locally originated
  EVPN network: [5]:[0]:[0]:[16]:[10.6.0.0]:[0.0.0.0] (VRF apple)
    10.10.41.2 (metric 0) from 0.0.0.0 (192.41.1.5)
      Origin IGP, MED not set, localpref 100, weight 32768
      Received label 2097154 2097154
      Extcommunity: 
          RT:1234:16777216

 Path-id 1 advertised to peers:
    50.41.50.1

The Shared RD line indicates the RD/VNI shared by the EVPN type-2 route and the BD subnet.

The EVPN Network line shows the EVPN type-5 route of the BD-Subnet.

The Path-id advertised to peers indicates the path advertised to EVPN peers.

Step 5

Verify that the EVPN peer (a DCIG) received the correct type-2 MAC-IP route and the host route was successfully imported into the given VRF, by entering a command such as the following on the DCIG device (assuming that the DCIG is a Cisco ASR 9000 switch in the example below):

Example:

RP/0/RSP0/CPU0:asr9k#show bgp vrf apple-2887482362-8-1 10.6.41.1
Tue Sep  6 23:38:50.034 UTC
BGP routing table entry for 10.6.41.1/32, Route Distinguisher: 44.55.66.77:51
Versions:
  Process           bRIB/RIB  SendTblVer
  Speaker               2088        2088
Last Modified: Feb 21 08:30:36.850 for 28w2d
Paths: (1 available, best #1)
  Not advertised to any peer
  Path #1: Received by speaker 0
  Not advertised to any peer
  Local
    192.41.1.1 (metric 42) from 10.10.41.1 (192.41.1.5) 
      Received Label 2097154
      Origin IGP, localpref 100, valid, internal, best, group-best, import-candidate, imported
      Received Path ID 0, Local Path ID 1, version 2088
      Community: 1234:444
      Extended community: 0x0204:1234:444 Encapsulation Type:8 Router 
MAC:0200.c029.0101 RT:1234:5101 
      RIB RNH: table_id 0xe0000190, Encap 8, VNI 2097154, MAC Address: 0200.c029.0101, 
IP Address: 192.41.1.1, IP table_id 0x00000000
      Source AFI: L2VPN EVPN, Source VRF: default, 
Source Route Distinguisher: 192.41.1.5:4123

In this output, the received RD, next hop, and attributes are the same for the type-2 route and the BD subnet.