To enable access between your VMs and the outside world, you can configure an external BGP (eBGP) connection between a tier-0 logical router and a router in your physical infrastructure.

About this task

When configuring BGP, you must configure a local Autonomous System (AS) number for the tier-0 logical router. For example, the following topology shows the local AS number is 64510. You must also configure the remote AS number of the physical router. In this example, the remote AS number is 64511. The remote neighbor IP address is 192.168.100.254. The neighbor must be in the same IP subnet as the uplink on the tier-0 logical router. BGP multihop is supported.

For test purposes, the 10.10.10.10/32 address is configured on the external router loopback interface.

Note:

Router ID used for forming BGP sessions on an edge node is autoselected from the IP addresses configured on the uplinks of a tier-0 logical router. BGP sessions on an edge node can flap when router ID changes. This can happen when the IP address auto-selected for router ID is deleted or the logical router port on which this IP is assigned is deleted.

Figure 1. BGP Connection Topology
BGP connection topology diagram

Prerequisites

Procedure

  1. From your browser, log in to an NSX Manager at https://nsx-manager-ip-address.
  2. Select Routing from the navigation panel.
  3. Select the tier-0 logical router.
  4. Click the Routing tab and select BGP from the drop-down menu.
  5. Click Edit.
    1. Configure the local AS number.

      For example, 64510.

    2. Click the Status toggle button to enable BGP.

      The Status button must be appear as Enabled.

    3. (Optional) : Click the ECMP toggle button to enable ECMP.
    4. (Optional) : Click the Graceful Restart toggle button to enable graceful restart.
    5. (Optional) : Configure route aggregation, enable graceful restart, and enable ECMP.

      Graceful restart is only supported if the edge cluster associated with the tier-0 router has only one edge node.

    6. Click Save.
  6. Click Add to add a BGP neighbor.
  7. Enter the neighbor IP address.

    For example, 192.168.100.254.

  8. (Optional) : Specify the maximum hop limit.

    The default is 1.

  9. Enter the remote AS number.

    For example, 64511.

  10. (Optional) : Configure the timers (keep alive time and hold down time) and a password.
  11. (Optional) : Click the Local Address tab to select a local address.
    1. (Optional) : Uncheck All Uplinks to see loopback ports as well as uplink ports.
  12. (Optional) : Click the Address Families tab to add an address family.
  13. (Optional) : Click the BFD Configuration tab to enable BFD.
  14. Click Save.

What to do next

Test whether BGP is working properly. See Verify BGP Connections from a Tier-0 Service Router.