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Refer to the exhibit. A company is expanding and decides to use a DMVPN solution to connect the branches. The network uses the EIGRP routing protocol. All remote branch routers must be configured with the normal EIGRP area. Auto-summary is not allowed on the routers in the network. Which solution must the company implement on R1 to achieve this goal?
The company must configure a summary route on R1. The branch routers must remain normal EIGRP routers, and auto-summary is not allowed, so the scalable design choice is manual summarization at the hub. Cisco EIGRP documentation states that manual summarization can be configured on an interface using the ip summary-address eigrp command and can summarize routes on almost any bit boundary. In a DMVPN hub-and-spoke topology, a hub summary reduces the number of individual routes advertised to branches, limits routing-table growth, and helps contain EIGRP queries. It also keeps branch configuration simple because the branches do not need to be converted to stub routers to meet this specific requirement. Disabling split horizon is a common DMVPN Phase 2 consideration when the hub must advertise spoke routes back out the same multipoint tunnel interface, but it does not summarize HQ routes. A multipoint interface is already implied by DMVPN, and disabling the SIA timer is not a design solution. Reference topics: EIGRP manual summarization, DMVPN hub design, no auto-summary, query containment.