Cisco Updated 300-410 Exam Questions and Answers by faris

We have an example of how to configure DMVPN Phase II and we show the configuration here for your reference:

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DMVPN Phase II – Dynamic Mapping

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Note: Although Phase II – Dynamic Mapping is “dynamic” but we still need to add a static entry for the hub because without that entry, the NHRP registration cannot be sent.

In an MPLS PE router, CE advertised routes are segmented from other CE routers by assigning CE-facing interfaces to different Virtual Routing and Forwarding (VRF) instances12. A VRF is a technology that allows multiple instances of a routing table to co-exist within the same router at the same time. By associating a network interface with a VRF, the network layer (Layer 3) has a different view of the network topology. This allows the segmentation of routing paths for traffic from different customers or different types of traffic. In the context of MPLS, VRFs are used to create separate routing instances for each customer on a PE router3.

We tested this config in GNS3 (except the LAN interface) but R1 loopback0 was advertised normally on R2 and R2 could reach this loopback0.

Note: Although the configured loopback address is 4.4.4.4/24 but by default OSPF will advertise this route to loopback0 as 4.4.4.4/32 (most specific route to that loopback). In order to override this, we have to change the network type to point-to-point. After this OSPF will advertise the address to loopback as 4.4.4.0/24.