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NET 132 CHAPTERS 7 7.1.6, 7.2.4,
QUESTIONS AND ANSWERS
To properly configure link-state routing, which of the following is mandatory within an area? Answer - ANSWER Backbone You are currently using EIGRP on your network. Which of the following would you gain by switching to OSPF? (Select two.) Answer - ANSWER Hierarchical network design Open standard You have configured Router A, Router B, and Router C as shown. No loopback interfaces have been configured. hostname C...router ospf 600network 172.16.32.1 0.0.0.0 area 100network 192.168.2.1 0.0.0.0 area 100... What is the default router ID of Router C? - ANSWER 192.168.2. What are DRs and BDRs used for when using the OSPF routing protocol? Answer - ANSWER Reduce routing table updates in a broadcast network. You have a medium-sized business network with twelve subnets (192.168.1.0/24 through 192.168.12.0/24). You use OSPF for your routing protocol. One Ethernet subnet has five routers, all in the same OSPF area as shown. You want to ensure that RouterC becomes the designated router on the subnet. Assuming that no additional configuration parameters are configured other than what is shown, how could you accomplish this task? (Select three. Each option is a complete solution.) - ANSWER For the interface connected to the 192.168.12.0/24 subnet , set the OSPF priority to 2.
For the OSPF process, set the router-id to 200.1.1.1. Change the IP address on the interface connected to the 192.168.12.0/24 subnet to 192.168.12.254. You are running OSPF as your routing protocol. One Ethernet subnet has five OSPF routers on the subnet. A partial configuration for two of the routers is shown. Both routers are connected to the subnet through the Fa0/1 interface. All interfaces are up. hostname RouterA!interface loopback0ip address 199.1.1. 255.255.255.255!interface FastEthernet0/0ip address 172.17.1. 255.255.255.192!interface FastEthernet0/1ip address 172.16.1. 255.255.255.128!router ospf 200network 172.16.1.128 0.0.0.127 area 0network 172.17.1.0 0.0.0.63 area 0!--additional output omitted hostname RouterB!interface FastEthernet0/0ip address 172.18.1. 255.255.255.192!interface FastEthernet0/1ip address 172.16.1. 255.255.255.128!router ospf 300network 172.16.1.128 0.0.0.127 area 0network 172.18.1.0 0.0.0.63 area 0!--additional output omitted Assuming that either RouterA or RouterB will become the DR, which one will be elected the - ANSWER RouterA will be the DR because of the loopback interface IP address. You are running OSPF as your routing protocol. One Ethernet subnet has five OSPF routers on the subnet. A partial configuration for two of the routers is shown below. Both routers are connected to the subnet through the Fa0/ interface. All interfaces are up. hostname RouterA!interface loopback0ip address 15.1.1. 255.255.255.255!interface FastEthernet0/0ip address 172.17.1. 255.255.255.192shutdown!interface FastEthernet0/1ip address 172.16.1. 255.255.255.128ip ospf priority 0!router ospf 200network 172.16.1. 0.0.0.127 area 0network 172.17.1.0 0.0.0.63 area 0!--additional output omitted hostname RouterB!interface FastEthernet0/0ip address 172.18.1. 255.255.255.192!interface FastEthernet0/1ip address 172.16.1.
RTR5 has the highest OSPF priority. Match each OSPF communication state on the left with its corresponding attributes on the right. Each state may be used once, more than once, or not at all. - ANSWER All of the information in the hello packet matches the router's settings. Init The routers negotiate how the data transfer will take place. Exstart The routers trade database descriptions. Exchange Both routers have matching databases. Full The router receives a hello packet and checks the information it contains. Attempt The routers exchange LSUs that contain LSAs. Loading A router receives a hello packet that includes its own RID in a list of neighbors. 2 - Way Which of the following is contained in an OSPF hello packet? (Select two.) Answer - ANSWER A list of the router's neighbors The router's RID RTR1, RTR2, and RTR3 have been configured to use the OSPF protocol. RTR and RTR2 are neighbors; RTR3 and RTR2 are also neighbors. RTR2 fails to receive a hello packet from RTR3 within the dead interval. Which happens next? - ANSWER RTR2 declares RTR3 to be down.
You have configured two routers (LondonA and LondonB) for OSPF routing. Serial0/0 on LondonA is connected to Serial0/1 on LondonB. The partial configuration of each router is shown below: hostname LondonA!interface Serial0/0ip address 172.17.1. 255.255.255.252encapsulation frame-relay!interface Serial0/1ip address 172.17.1.161 255.255.255.248encapsulation frame-relay!router ospf 300network 172.17.1.76 0.0.0.3 area 100network 172.17.1.160 0.0.0.7 area 100! --additional output omitted hostname LondonB!interface Serial0/0ip address 172.17.1. 255.255.255.248encapsulation frame-relay!interface Serial0/1ip address 172.17.1.77 255.255.255.252encapsulation frame-relay!router ospf 200network 172.17.1.16 0.0.0.7 area 10network 172.17.1.76 0.0.0.3 area 10! --additional output omitted When you check the routing table on LondonA, you find that it has not learned about network 172.17.1.16 from LondonB. What is the problem? - ANSWER The areas defined in the network statements do not match. Which of the following does OSPF use to create and maintain routing tables? (Select three.) Answer - ANSWER Topology exchange Route identification Neighbor discovery You want to change the amount of time it takes for a hello packet to not be received before a router is declared offline. Which setting do you need to change? - ANSWER Dead interval During which state in the OSPF communication process are link-state databases exchanged? - ANSWER 2-way Which of the following are considered stable neighbor states? (Select two.) Answer - ANSWER 2-way
encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.77 255.255.255. encapsulation frame-relay ! router ospf 200 network 172.17.1.16 0.0.0.7 area 100 network 172.17.1.76 0.0.0.3 area 100 ! --additional output omitted When you check the routing table on LondonA, you find that it has not learned about network 172.17.1.16 from Lo - ANSWER The IP address assigned to Serial0/0 on LondonA is not on the same subnet as the IP address assigned to Serial0/1 on LondonB. You want to prevent all interfaces on a router from sending or responding to OSPF Hello messages. Which command should you use? - ANSWER passive-interface default You are configuring OSPF for Area 0. SubnetA uses an address of 172.16.20.48/28. Which wildcard mask value would you use for the network statement? Answer - ANSWER 0.0.0. You are configuring OSPF for a single router with two interfaces, as shown in the image. Which network statement(s) would you use to configure both interfaces for OSPF for area 0? - ANSWER network 192.168.1.64 0.0.0.31 area 0 network 192.168.1.128 0.0.0.15 area 0 You want to configure OSPF to run only on the interface with an IP address of 10.1.1.112/26, and you want to associate the interface with Area 3. Which of the following commands will accomplish your goal? - ANSWER network 10.1.1.64 0.0.0.63 area 3
You have configured two routers (LondonA and LondonB) for OSPF routing. Serial0/0 on LondonA is connected to Serial0/1 on LondonB. The partial configuration of each router is shown below: hostname LondonA ! interface Serial0/ ip address 172.17.1.78 255.255.255. encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.161 255.255.255. encapsulation frame-relay ! router ospf 300 network 172.17.1.76 0.0.0.3 area 100 network 172.17.1.160 0.0.0.7 area 100 ! --additional output omitted hostname LondonB ! interface Serial0/ ip address 172.17.1.17 255.255.255. encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.77 255.255.255. encapsulation frame-relay ! router ospf 200 network 172.17.1.16 0.0.0.3 area 100 network 172.17.1.76 0.0.0.7 area 100 ! --additional output omitted When you check the routing table on LondonA, you find that it has not learned about network 172.17.1.16 from Lo - ANSWER Wildcard mask values for the network statements are incorrect.
Match each OSPF component on the left with its corresponding description on the right. Each component may be used once, more than once, or not at all. - ANSWER The OSPF area to which all the other areas connect. Backbone area A router in the backbone area. Backbone router A router in a single, non-backbone area. Internal router : Known as area 0. Backbone area : A set of routers and links that share the same link-state database information. Area An OSPF router that connects two areas. Area border router Has interfaces connected to the backbone area and to at least one other area. Area border router You want to configure Router B to run OSPF with a local process ID of 100. Both interfaces S0 and S1 on Router B belong to area 300. Which set of commands should you enter? - ANSWER router ospf 100network 172.16.16. 0.0.0.0 area 300network 172.16.32.2 0.0.0.0 area 300 Match each OSPF database on the left with the corresponding description on the right. Each database may be used once, more than once, or not at all. - ANSWER Contains LSAs and lists all possible routes. Topology Lists all the neighbors that the router has learned about from the hello packets. Adjacency Built from the information gathered in the adjacency database. Topology
Built from the information in the topology database. Routing table Lists the best possible route calculated from the SPF algorithm. Routing table Also known as the neighbor relationship table. Adjacency Match each route type on the left with its default administrative distance on the right - ANSWER 0 Connected 1 Static 20 BGP 90 EIGRP 110 OSPF 120 RIP A set of routers and links that share the same link-state database information is known as what? - ANSWER Area Which of the following connects two areas? - ANSWER Area border router Which of the following describes a Type 2 LSA? - ANSWER Describes a network that has a DR and BDR.
hostname LondonB ! interface Serial0/ ip address 172.17.1.17 255.255.255. encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.77 255.255.255. encapsulation frame-relay ! router ospf 200 network 172.17.1.16 0.0.0.7 area 100 network 172.17.1.76 0.0.0.3 area 100 ! --additional output omitted When you check the routing table on LondonA, you find that it has not learned about network 172.17.1.16 from Lond - ANSWER The IP address assigned to Serial0/0 on LondonA is not on the same subnet as the IP address assigned to Serial0/1 on LondonB. You want to prevent all interfaces on a router from sending or responding to OSPF Hello messages. Which command should you use? - ANSWER passive-interface default You are configuring OSPF for Area 0. SubnetA uses an address of 172.16.20.48/28. Which wildcard mask value would you use for the network statement? - ANSWER 0.0.0. Listen to exam instructions You are configuring OSPF for a single router with two interfaces, as shown in the image. Which network statement(s) would you use to configure both interfaces for OSPF for area 0? - ANSWER network 192.168.1.64 0.0.0.31 area 0 network 192.168.1.128 0.0.0.15 area 0 You want to configure OSPF to run only on the interface with an IP address of 10.1.1.112/26, and you want to associate the interface with Area 3. Which of the
following commands will accomplish your goal? - ANSWER network 10.1.1.64 0.0.0.63 area 3 You have configured two routers (LondonA and LondonB) for OSPF routing. Serial0/0 on LondonA is connected to Serial0/1 on LondonB. The partial configuration of each router is shown below: hostname LondonA ! interface Serial0/ ip address 172.17.1.78 255.255.255. encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.161 255.255.255. encapsulation frame-relay ! router ospf 300 network 172.17.1.76 0.0.0.3 area 100 network 172.17.1.160 0.0.0.7 area 100 ! --additional output omitted hostname LondonB!interface Serial0/ ip address 172.17.1.17 255.255.255. encapsulation frame-relay ! interface Serial0/ ip address 172.17.1.77 255.255.255. encapsulation frame-relay ! router ospf 200 network 172.17.1.16 0.0.0.3 area 100 network 172.17.1.76 0.0.0.7 area 100 ! --additional output omitted When you check the routing table on LondonA, you find that it has not learned about network 172.17.1.16 from Londo - ANSWER Wildcard mask values for the network statements are incorrect.
Supports multiple protocols. You are currently using OSPF on your network. Which of the following would you gain by switching to EIGRP? (Select three.) - ANSWER Multiprotocol support Auto-summarization Faster recovery from primary link failure Which of the following are true of EIGRP configuration to enable two routers to become adjacent? (Select two.) - ANSWER Authentication parameters must match. The area number used to configure EIGRP must match. Match each routing protocol characteristic on the left with the associated routing protocol on the right. - ANSWER EIGRP Characteristics Supports auto-summarization Unequal-cost load balancing DUAL OSPF Characteristics Open standard DR and BDR Dijkstra SPF EIGRP uses a neighbor's table to keep track of neighbor routers. Which of the following helps the router identify cost values to reach each neighbor in the routing table? - ANSWER Round-trip timers What is the total distance to a destination through a specific neighbor router is known as? - ANSWER Computed distance What does EIGRP use to send partial routing updates? - ANSWER RTP Which IP address does EIGRP send routing updates to? - ANSWER 224.0.0.
Which algorithm does EIGRP use to choose an alternate route when a route fails and there is no feasible successor? - ANSWER DUAL Where are all known routes to a destination kept? Answer - ANSWER Topology table 7.4.5 - ANSWER What are the minimum commands you must use to configure EIGRP on a router,? (Select two.) Answer - ANSWER network 1.0.0. router eigrp 12 You want to configure RouterB to run EIGRP. The networks attached to both interfaces S0 and S1 on RouterB are to be advertised within Autonomous System 100. Which set of commands should you enter? - ANSWER router eigrp 100 network 172.16.0. network 172.17.0. You are reviewing the configuration of a router that uses EIGRP for its routing protocol. Shown below is the output from the show ip protocols command: Routing Protocol is "eigrp 1" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Default networks flagged in outgoing updates Default networks accepted from incoming updates EIGRP metric weight K1=1, K2=0, K3=1, K4=0, K5= EIGRP maximum hopcount 100 EIGRP maximum metric variance 2 Redistributing: eigrp 1 EIGRP NSF-aware route hold timer is 240s Automatic network summarization is in effect Maximum path: 5 Routing for Networks: 192.168.1. 192.168.2.
You have configured EIGRP routing on RouterA. A partial configuration is shown below: hostname RouterA ! interface FastEthernet 0/ ip address 192.168.1.65 255.255.255. duplex auto speed auto ! interface FastEthernet 0/ ip address 192.168.1.97 255.255.255. duplex auto speed auto ! interface Serial 0/1/ ip address 10.21.177.85 255.255.255. encapsulation ppp ! router eigrp 100 network 192.168.1. network 10.0.0. auto-summary ! RouterA is connected to RouterB through the serial link. When you check the routing table on RouterA, you see a single route reported learned though EIGRP to network 192.168.1.0/24. You want RouterA to have routes to the individual networks connected to RouterA. How should you modify the configuration of RouterA? - ANSWER Use the no auto-summary command. You are reviewing the configuration of a router that uses EIGRP for its routing protocol. Shown below is the output from the show ip eigrp topology all-links command: Router# show ip eigrp topology all-links IP-EIGRP Topology Table for process 77 Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply, r - Reply status
P 172.16.90.0 255.255.255.0, 2 successors, FD is 46251776 via 172.16.80.28 (46251776/46226176), Ethernet via 172.16.81.28 (46251776/46226176), Ethernet via 172.16.80.31 (46277376/46251889), Serial P 172.16.81.0 255.255.255.0, 1 successors, FD is 307200 via 172.16.82.28 (307200/281600), Ethernet via 172.16.80.28 (308500/281600), Ethernet via 172.16.80.31 (332800/307900), Serial Based on the output, which of the following is true for the route to network 172.16.81.0/24? - ANSWER The route through Ethernet1 is the successor route. In which type of network must packets being sent between subnets pass through one or more subnets of a different network? - ANSWER Discontiguous What is the maximum number of paths equal load balancing can support? - ANSWER 16 Which subcommand can be used to add more routes to the table for additional balancing? - ANSWER maximum-paths 7.3. You want to configure a single area OSPF network for area 0. What are the minimum commands you must use? (Select two.) - ANSWER network 1.1.1. 0.0.0.255 area 0 router ospf 12 7.7. You have configured EIGRP routing on RouterA. A partial configuration is shown below: hostname RouterA ! interface FastEthernet 0/ ip address 172.16.1.65 255.255.255.
