Remote Tunnel endpoint (RTEP) BGP neighborship is down alarm

Products

• VMware NSX

Issue/Introduction

Title: Alarm to indicate that the status of the remote tunnel endpoint (RTEP) BGP neighborship is down.

Event ID: rtep_bgp_down

Alarm Description:

• Purpose: To notify the admin that the BGP neighborship on the remote tunnel endpoint (RTEP) went down.
• Impact: BGP neighborship on the RTEP going down would cause the routes from the peer to be withdrawn and cause potential traffic disruptions within the network.

Environment

VMware NSX

Resolution

Steps to Resolve

For 4.0.0 and higher

 

Recommended Action: 

• Check for connectivity-related issues:
  • Perform a ping test from the edge node interface or the external peer.

    • Invoke the NSX CLI command get logical-routers.

      Sample CLI output: get logical-routers

      fed> get logical-router Logical Router UUID                                   VRF    LR-ID    Name                             Type                      Ports   Neighbors      ########-####-####-####-############                   0      0                                        TUNNEL                      3       2/5000         ########-####-####-####-############                   1      1      REMOTE_TUNNEL_VRF                 RTEP_TUNNEL                 4       2/50000        ########-####-####-####-############                   3      5      DR-Tier0Gateway1                  DISTRIBUTED_ROUTER_TIER0    6       0/50000        ########-####-####-####-############                   4      7      SR-Tier0Gateway1                  SERVICE_ROUTER_TIER0        6       3/50000

    • Switch to the REMOTE_TUNNEL_VRF {remote_tunnel_vrf_id} using the CLI command vrf remote_tunnel_vrf_id. 

    • Invoke the NSX CLI command get interfaces and check if the correct RTEP IP address is assigned to the interface with the name remote-tunnel-endpoint.

      Sample CLI output: get interfaces

      fed(remote_tunnel_vrf[1])> get interfaces Logical Router UUID                                   VRF    LR-ID  Name                              Type                       ########-####-####-####-############   1      1      REMOTE_TUNNEL_VRF                 RTEP_TUNNEL                Interfaces (IPv6 DAD Status A-DAD_Success, F-DAD_Duplicate, T-DAD_Tentative, U-DAD_Unavailable)     Interface     ########-####-####-####-############     Ifuid             Mode          : cpu     Port-type     : cpu     Enable-mcast  : false       Interface     ########-####-####-####-############     Ifuid             Mode          : blackhole     Port-type     : blackhole       Interface     ########-####-####-####-############     Ifuid             Name          : remote-tunnel-endpoint     Fwd-mode      : IPV4_ONLY     Internal name : uplink-268     Mode          : lif     Port-type     : uplink     IP/Mask       : ##.##.##.##/24;####:##::#/64(NA)     MAC           ##:##:##:##:##:##     VLAN              Access-VLAN   : untagged     LS port       : ########-####-####-####-############     Urpf-mode     : PORT_CHECK     DAD-mode      : LOOSE     RA-mode       : RA_INVALID     Admin         : up     Op_state      : up     Enable-mcast  : False     MTU               arp_proxy     :       Interface     ########-####-####-####-############     Ifuid             Mode          : loopback     Port-type     : loopback     IP/Mask       : 127.0.0.1/8;::1/128(NA)

    • Issue the command ping <remote_tunnel_endpoint> 
    • If the ping fails,
      • Check VLAN on the segment/Edge logical uplink and the vlan on the external Peer interface. If the vlan configuration does not match, ping failure is expected. 
        • Identify the correct vlan that needs to be configured and ensure 

          the RTEP VLAN by logging to NSX and navigating to System | Fabric | Nodes | Select Relevant TN | Tunnels | RTEP VLAN.

        • Check RTEP MTU by navigating to System | Fabric | Settings | Remote Tunnel Endpoint MTU

    • If the ping is successful, 
      • check for any firewall rules configured to block the BFD control packets.
      • check BGP configuration on the peer.
  • Check for MTU related Issues:
    • • • Check MTU setting on the TOR interface connected to the physical NIC of the DVS uplink which provides connectivity to the Tier-0 uplink.
        • You can find the NSX MTU guidance here: Guidance to Set Maximum Transmission Unit. 
        • Follow procedures in the KB article 317210 to address common NSX underlying infrastructure connectivity issues.