Choosing Between Three Routes to Same Subnet
Today’s question focuses on one router that has three different available routes to the same subnet (10.1.2.0/24). Which should it choose? Details below, and answer in a few days.
R1 happens to run RIP-2 over the link to R2, OSPF over the link to R3, and EIGRP over the link to R4. All three of the routers on the right advertise a route for 10.1.2.0/24. R1’s metric for the RIP-2 route is 1; with OSPF the metric is 65; and for EIGRP, the metric is 2,168,134.
The first question: Which router will R1 choose? And Why?
Next, R1 is configured with a static IP route for 10.1.2.0/24, with the next-hop router configured as R2, R3, or R4. Which one? Pick whichever router you didn’t pick as the answer to the first question. Which route, and which next-hop router, does R1 use now for packets destined for 10.1.2.0/24?
1)R4 will be preferred due to lowest AD. Metrics are irrelevant here.
2) The static route will be preferred over any of the learned routes, again due to lowest AD.
Thanks Dave for the post. The answers post is now up as well. But I agree!
Wendell