The Route Target

The route target determines which routes are inserted into a VRF. A VRF can be configured for one or more route targets for import, export, or both. At least one configured route target for import or export is a required component when defining a L3 VPN VRF. All routes exported by the VRF are tagged with each route target identifier configured for export on the VRF. Only VRFs configured to import routes tagged with the route target identifier will import the route. This allows you to configure one VRF to export multiple route targets and another VRF to be configured to import only a subset of the routes the first VRF exports.

This example shows how to export VPN address family prefixes and tag them with route target 1:1000:

System(su)->router vpnA
System(su-vpnA)->configure
System(su-vpnA-config)->route-target export 1:1000
System(su-vpnA-config)->

This example shows how to both import BGP VPN updates tagged with the route target 10.10.176.25:1000 and tag any BGP VPN advertisements with the route target 10.10.176.25:1000:

System(su)->router vpnA
System(su-vpnA)->configure
System(su-vpnA-config)->route-target both 10.10.176.25:1000
System(su-vpnA-config)->