A route map consists of a sequence of IP prefix lists, BGP path attributes, and an associated action. The router scans the sequence for an IP address match. If there is a match, the router performs the action and scans no further.

Route maps can be referenced at the BGP neighbor level and route redistribution. When IP prefix lists are referenced in route maps and the route map action of permitting or denying is applied, the action specified in the route map sequence overrides the specification within the IP prefix list.

Prerequisites

Procedure

  1. With admin privileges, log in to NSX Manager.
  2. Select Networking > Tier-0 Logical Routers.
  3. Select the tier-0 logical router.
  4. Select Routing > Route Maps.
  5. Click Add.
  6. Enter a name and an optional description for the route map.
  7. Click Add to add an entry in the route map.
  8. Edit the column Match IP Prefix List/Community List to select either IP prefix lists, or community lists, but not both.
  9. (Optional) Set BGP attributes.
    BGP Attribute Description
    AS-path Prepend Prepend a path with one or more AS (autonomous system) numbers to make the path longer and therefore less preferred.
    MED Multi-Exit Discriminator indicates to an external peer a preferred path to an AS.
    Weight Set a weight to influence path selection. The range is 0 - 65535.
    Community Specify a community using the aa:nn format, for example, 300:500. Or use the drop-down menu to select one of the following:
    • NO_EXPORT_SUBCONFED - Do not advertise to EBGP peers.
    • NO_ADVERTISE - Do not advertise to any peer.
    • NO_EXPORT - Do not advertise outside BGP confederation
  10. In the Action column, select Permit or Deny.
    You can permit or deny IP addresses in the IP prefix lists from advertising their addresses.
  11. Click Save.