350-401 Practice Question: Ip vrf RED rd 200:1 route-target export 200:1…

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✓

  The configuration is correct for MPLS L3VPN, but the VRF RED must also be configured under BGP with 'address-family ipv4 vrf RED'.

  Why this is correct

  The statement is correct: for an MPLS L3VPN, the VRF RED configuration itself is valid, but the VRF must also be activated in BGP under the 'address-family ipv4 vrf RED' stanza. This enables BGP to import and export routes between the VRF and the VPNv4 address family, converting IPv4 VRF routes into VPNv4 routes with the appropriate route target extended communities. Without this BGP address-family configuration, the VRF will have no BGP peering for VPN routes, so even if other pieces are in place, end-to-end L3VPN connectivity will not work.

• ✗

  The 'send-community extended' command is unnecessary because it is enabled by default.

  Why it's wrong here

  This is incorrect because 'send-community extended' is not enabled by default in BGP. BGP community exchange requires explicit configuration: 'neighbor X.X.X.X send-community' for standard communities and 'neighbor X.X.X.X send-community extended' for extended communities. In an MPLS L3VPN, route targets are carried as BGP extended communities, and without this command the VPNv4 routes will be sent without the critical route target attributes, making it impossible for receiving PEs to import the routes into any VRF.

• ✗

  The interface GigabitEthernet0/1 requires 'mpls ip' to forward MPLS packets.

  Why it's wrong here

  This is incorrect because GigabitEthernet0/1 is a customer-facing (CE-facing) interface, and MPLS encapsulation is not required on such links. In MPLS L3VPN, MPLS is deployed only on core-facing interfaces between PE and P routers (or PE to PE) to carry labeled VPN packets across the service provider backbone. The CE-facing interface simply runs normal IP routing in the VRF; enabling 'mpls ip' there would be unnecessary and could cause the router to try to label-switch traffic toward the CE, which is not how L3VPN is designed.

• ✗

  The VRF RED will automatically import routes from the VPNv4 address-family without additional configuration.

  Why it's wrong here

  This is incorrect because the VRF does not automatically import routes from the VPNv4 address family. Importing and exporting VPN routes is controlled by route target (RT) extended communities, but the BGP process must first be explicitly configured with 'address-family ipv4 vrf RED' and the appropriate RD/RT values. Even if RTs are correctly defined in the VRF, the PE router will not exchange VPNv4 routes unless BGP has an active VPNv4 session and the VRF is explicitly activated under BGP; no automatic import occurs without that explicit configuration.

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