642-902 Q&A – Implement an EIGRP based solution (16-20)

Section1 – Implement an EIGRP based solution, given a network design and a set of requirements

Refer to the exhibit and the partial configuration on router R2. On router R4 all RIP routes are redistributed into the OSPF domain. A second redistribution is configured on router R2 using a route map. Based on the configuration on router R2, which EIGRP external routes will be present in the routing table of R1? Select the best response.

A. the routes originating from the RIP routing domain
B. the routes originating from the OSPF stub area
C. all OSPF inter and intra-area routes
D. all routes originating from RIP and OSPF routing domains
Answer: A

Refer to the exhibit. EIGRP is configured on all routers in the network. On a basis of the show ip eigrp topology output provided, what conclusion can be derived?

A. Router R1 is waiting for a reply from the neighbor to the hello message sent out inquiring for a second successor to network
B. Router R1 can send traffic destined for network out of interface FastEthernet0/0.
C. Router R1 is waiting for a reply from the neighbor to the hello message sent out before it declares the neighbor unreachable.
D. Router R1 is waiting for a reply from the neighbor in response to the query sent out about network
Answer: D
The “show ip eigrp topology” command lists all routes that EIGRP is aware of and shows whether
EIGRP is actively processing information on that route. Under most normal conditions, the routes should all be in a passive state and no EIGRP process are running for that route. If the routes are active, this could indicate the dreaded stuck in active, or SIA, state.
The fields to note in this output are as follows: P- Passive; no EIGRP computation is being performed. This is the ideal state. A- Active; EIGRP computations are “actively” being performed for this destination. Routes constantly appearing in an active state indicate a neighbor or query problem. Both are symptoms of the SIA problem. U- Update; an update packet was sent to this destination. Q- Query; a query packet was sent to this destination. R- Reply; a reply packet was sent to this destination. Route information- IP address of the route or network, its subnet mask, and the successor, or next hop to that network, or the feasible successor.

Which statement about a non-zero value for the load metric (k2) for EIGRP is true? Select the best response.
A. A change in the load on an interface will cause EIGRP to recalculate the routing metrics and send a corresponding update out to each of its neighbors.
B. EIGRP calculates interface load as a 5-minute exponentially weighted average that is updated every 5 minutes.
C. EIGRP considers the load of an interface only when sending an update for some other reason.
D. A change in the load on an interface will cause EIGRP to recalculate and update the administrative distance for all routes learned on that interface.
Answer: C

Refer to the exhibit. Router RTA is the hub router for routers RTB and RTC. The Frame Relay network is configured with EIGRP, and the entire network is in autonomous system 1. However, router RTB and RTC are not receiving each other’s routes. What is the solution?

A. Check and change the access lists on router RTA.
B. Configure the auto summary command under router eigrp 1 on router RTA.
C. Configure subinterfaces on the spoke routers and assign different IP address subnets for each subinterface.
D. Issue the no ip split horizon command on router RTA.
E. Issue the no ip split horizon eigrp 1 command on router RTA.
F. Configure a distribute list on router RTA that allows it to advertise all routes to the spoke routers.
Answer: E
Split horizon controls the sending of EIGRP update and query packets. When split horizon is enabled on an interface, these packets are not sent for destinations for which this interface is the next hop. This reduces the possibility of routing loops.
By default, split horizon is enabled on all interfaces.
Split horizon blocks route information from being advertised by a router out of any interface from which that information originated. This behavior usually optimizes communications among multiple routing devices, particularly when links are broken. However, with nonbroadcast networks (such as Frame Relay and SMDS), situations can arise for which this behavior is less than ideal. For these situations, you may want to disable split horizon. In this example, routes received by RTB and RTC are not being sent back out the same serial interface on RTA, so they are not receiving each other’s routes. Disabling Split horizons on interface S0/0 on RTA will fix this issue.

Refer to the exhibit. Router B and router C are performing mutual redistribution between OSPF and EIGRP, and their default metrics are configured the same. Router D has equal cost paths to networks where both paths are not really equal cost. For example, network shows equal cost through both router B and router C, though in reality the cost is greater using router C.

Other routers, though not shown, are connected to the and networks, and the same issues exist to those routers and the networks connected to them. What can be done so that data will be routed along the most optimal path in the network? Select the best response.
A. Redistribute connected interfaces on router B and router C.
B. Set the maximum number of equal cost paths to1 in all routers.
C. When redistributing EIGRP into OSPF, set the external metric type to type E1.
D. Adjust the default metrics in router B and router C so that the values are different in each router.
E. None of these solutions will fix the problem. Migrate to a single dynamic routing protocol.
Answer: E