Dell C1048P Port Extender Networking Configuration Guide for the C9000 Series - Page 972

While importing these routes into VRF-blue, you can further specify match conditions at the import end to define the filtering criteria based on which the routes are imported into VRF-blue. You can define a route-map import_ospf_protocol and then specify the match criteria as OSPF using the match source-protocol ospf command. You can then use the ip route-import route-map command to import routes matching the filtering criteria defined in the import_ospf_protocol route-map. For a reply communication, VRF-blue is configured with a route-export tag. This value is then configured as route-import tag on the VRF-Red. To configure route leaking using filtering criteria, perform the following steps: 1 Configure VRF-red using the following command:ip vrf vrf-redip vrf forwarding vrf-redip address x.x.x.x 255.x.x.x A non-default VRF named VRF-red is created and the interface 1/11 is assigned to this VRF. 2 Define a route-map export_ospfbgp_protocol.Dell(config)route-map export_ospfbgp_protocol permit 10 3 Define the matching criteria for the exported routes.Dell(config-route-map)match source-protocol ospfDell(config-route-map)match source-protocol bgp This action specifies that the route-map contains OSPF and BGP as the matching criteria for exporting routes from vrf-red. 4 Configure the export target in the source VRF with route-map export_ospfbgp_protocol.ip route-export 1:1 export_ospfbgp_protocol 5 Configure VRF-blue.ip vrf vrf-blue ip vrf forwarding VRF-blueip address x.x.x.x 255.x.x.x A non-default VRF named VRF-blue is created and the interface 1/22 is assigned to it. 6 Define the route-map import_ospf_protocol.Dell(config)route-map import_ospf_protocol permit 10 7 Define the matching criteria for importing routes into VRF-blue.Dell(config-route-map)match source-protocol ospf This action specifies that the route-map contains OSPF as the matching criteria for importing routes into vrf-blue. 8 Configure the import target in VRF-blue with route-map import_ospf_protociol.ip route-import 1:1 import_ospf_protocol When you import routes into VRF-blue using the route-map import_ospf_protocol, only OSPF routes are imported into VRF-blue. Even though VRF-red has leaked both OSPF as well as BGP routes to be shared with other VRFs, this command imports only OSPF routes into VRF-blue. 9 Configure the import target in the source VRF for reverse communnication with the destination VRF.ip route-import 2:2 The show run output for the above configuration is as follows: ip vrf vrf-Red ip route-export 1:1 export_ospfbgp_protocol ip route-import 2:2 ! this action exports only the OSPF and BGP routes to other VRFs ! ip vrf vrf-Blue ip route-export 2:2 ip route-import 1:1 import_ospf_protocol !this action accepts only OSPF routes from VRF-red even though both OSPF as well as BGP routes are shared The show VRF commands displays the following output: Important Points to Remember • Only Active routes are eligible for leaking. For example, if VRF-A has two routes from BGP and OSPF, in which the BGP route is not active. In this scenario, the OSPF route takes precedence over BGP. Even though the Target VRF-B has specified filtering options to match BGP, the BGP route is not leaked as that route is not active in the Source VRF. • The export-target and import-target support only the match protocol and match prefix-list options. Other options that are configured in the route-maps are ignored. • You can expose a unique set of routes from the Source VRF for Leaking to other VRFs. For example, in VRF-red there is no option for exporting one set of routes (for example, OSPF) to VRF- blue and another set of routes (for example, BGP routes) to some other VRF. Similarly, when two VRFs leak or export routes, there is no option to discretely filter leaked routes from each source VRF. Meaning, you cannot import one set of routes from VRF-red and another set of routes from VRF-blue. Virtual Routing and Forwarding (VRF) 972