Chapter 6

The administrative distance determines the trustworthiness of the route source. Assuming that two separate routes are available to the same location, the router will use the following criteria for choosing between these routes. Put the criteria in order.

1.) If a static route is available, it is selected. 2.) If a router has learned of two routes to a single network through different routing protocols, it chooses the route with the lowest administrative distance. 3.) If a router has learned of two routes through the same protocol, the router will choose the route that has the best cost as defined by the routing metric.

IP traffic destined for a device configured with the address 10.10.34.4/24 is congesting the network. The network administrator issues a traceroute command from the local router and receives the following output: Router#traceroute 10.10.34.4 Type escape sequence to abort.Tracing the route to 10.10.34.4 1 192.168.12.2 20 msec 20 msec 20 msec2 192.168.12.1 8 msec 12 msec 8 msec3 192.168.12.2 8 msec 8 msec 12 msec4 192.168.12.1 12 msec 8 msec 8 msec5 192.168.12.2 8 msec 8 msec 12 msec6 192.168.12.1 8 msec 12 msec 8 msec ! -- remaining output omitted -- What is the cause of the problem?

A loop exists between two of the routers.

Which Cisco express forwarding mechanism maintains Layer 2 information linked to a particular entry in the routing table, reducing the need to send ARP requests before forwarding packets?

Adjacency tables

A network administrator is located in a subnet connected to Switch P1 as shown. The administrator is unable to ping Switch A1 connected to the Atlanta router. What is the cause of the problem?

An incorrect default-gateway address is configured on Switch A1.

Network users are complaining that they can connect to resources within the company, but cannot use the internet. The network administrator begins troubleshooting the problem by entering privileged EXEC mode on the company router and typing the show ip route command. What is the most probable cause of the problem?

An incorrect next-hop route is statically configured on the local router.

Which of the following is an EGP that an ISP uses to send packets across the internet from one internal network to another?

Border Gateway Protocol (BGP)

You have a small network as shown in the Exhibit. You are unable to ping Wrk2 from Wrk1. What should you do to fix the problem?

Change the IP address assigned to Wrk2.

Which internal routing logic organizes routing data using a tree structure, which allows very fast searches and requires less time to route packets?

Cisco express forwarding

The administrator of a corporate network is receiving complaints from internal users that they cannot access the internet. The administrator displays the routing table of the local router using the show ip route command. What should the administrator do on the local router to provide internal users access to the internet?

Configure a default route using ip route 0.0.0.0 0.0.0.0 131.108.2.2.

You are working at the console of a new router. You want to check the configuration of a neighboring router called Sales5. You type telnet Sales5 at the router prompt and receive the following message: Translating "Sales5"...domain server (255.255.255.255)% Unknown command or computer name, or unable to find computer address What should you do?

Configure an address of a DNS server for the router to contact.

You have a small network as shown. You have configured RIP on both RouterA and RouterB. The show ip route command on RouterA shows the following information: Codes: C - connected, S - static, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter areaN1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2E1 - OSPF external type 1, E2 - OSPF external type 2i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2ia - IS-IS inter area, * - candidate default, U - per-user static routeo - ODR, P - periodic downloaded static route Gateway of last resort is not set R 10.0.0.0/8 [120/1] via 192.168.4.2, 00:00:02, FastEthernet0/1C 192.168.1.0/24 is directly connected, FastEthernet0/0C* 192.168.4.0/24 is directly connected, FastEthernet0/1C 192.168.2.0/24 is directly connected, FastEthernet0/2 RouterA receives a packet addressed to 172.16.0.1. What will RouterA do with the packet?

Drop the packet.

Match each default administrative distance with the correct route type. (Each item may be used once, more than once, or not at all.)

EIGRP internal routes : 90 EIGRP external routes : 170 OSPF : 110 RIP : 120 Static routes : 1

Router_1 is connected to three networks, 192.168.0.0, 172.16.16.0, and 172.16.32.0. An administrator enables the RIP routing protocol on Router_1. The router isn't forwarding packets to network 172.16.16.0. The administrator examines the configuration on Router_1 using the sh run command. What should the administrator do to correct the problem?

Enable the Serial0 interface.

When attempting to make a Telnet connection to a remote router, the connection fails. You check the interface status on your local router and find the following: Serial0/1/0 is up, line protocol is upHardware is GT96K SerialInternet address is 192.168.2.1/24MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,reliability 255/255, txload 1/255, rxload 1/255Encapsulation HDLC, loopback not setKeepalive set (10 sec)... (additional output omitted) You ping the remote router, but that fails as well. At which layer of the OSI model does this problem originate?

Layer 3

Which protocol can have a higher Memory and CPU requirement than the others?

OSPF

Which protocol was created in the 1980s, was improved over the years, and is still used for small networks?

RIP

Which of the following is a disadvantage of static routing?

Require more configuration time

Kathy executed the show interfaces command on a router and reviewed the output. Which output indicates a Layer 1 problem with the Serial0/1/1 interface?

Serial0/1/1 is down, line protocol is down.

Paul executed the show interfaces command and reviewed the output. Which output indicates a Layer 2 problem with the Serial0/1/1 interface?

Serial0/1/1 is up, line protocol is down.

Which of the following methods of preventing the count-to-infinity problem with distance vector routers will send a hop count of 16 back up the path from which the information was obtained?

Split horizon with poison reverse

You are the administrator of the network shown. You want to configure the stub network located in Tampa to forward packets to Chicago, but you do not want the overhead associated with a routing protocol. Which of the following will accomplish your goal?

Tampa(config)#ip route 0.0.0.0 0.0.0.0 182.1.48.3Chicago(config)#ip route 182.1.48.0 255.255.240.0 182.1.48.4Chicago(config)#ip route 192.168.112.128 255.255.255.248 182.1.48.4

RouterA, RouterB, and RouterC have been configured with IP addresses set as shown. All networks are using the default subnet mask. Users in network 10.1.1.0 claim they cannot access resources in network 192.168.2.0. From network 10.1.1.0, you can successfully ping interface 172.16.32.2, but you cannot ping 172.16.32.1. Another administrator on 192.168.2.0 claims she can ping 192.168.2.1, but not 172.16.32.1. What is most likely the problem?

The S0/1/1 interface on Router C is administratively down.

Last night, an administrator connected a new router to his network and enabled the RIP routing protocol. This morning, when the administrator returned, he discovered the router wasn't forwarding packets to networks connected to the Serial1 interface. He examines the routing table using the command show ip route. What could be the cause of the problem?

The Serial1 interface is administratively shut down.

Which of the following best describes a hop count?

The number of routers needed to get to the destination network.

You have a small network as shown. The user on workstation A reports that she cannot communicate with remote workstation D. You begin to troubleshoot the problem by sending a ping from workstation A to the remote workstation D, but it does not reply. Next, you try sending a ping from workstation A to the remote workstation C, and it replies successfully. Which of the following can you assume based on these results?

The problem is with the configuration or connectivity of remote workstation D.

How does a router use frames to route data through a network?

The router checks the MAC address in the frame, replaces the MAC address of the source with its own MAC address, and sends it to the proper host.

Which of the following best describes how a router operates to transmit messages to different LAN segments?

The router reads the LAN segment address contained in the message and consults the appropriate routing table for the protocol, then forwards the message to the appropriate LAN segment.

You have just connected a Windows workstation to the network. The workstation can communicate with all devices on the same subnet, but can't communicate with other devices on other subnets. You use the ipconfig command on the workstation and see the following: C:\ipconfigWindows IP ConfigurationEthernet adapter Local Area Connection:IP Address . . . . . . . . . . : 192.168.1.100Subnet Mask. . . . . . . . . . : 255.255.255.0Default Gateway. . . . . . . . : 192.168.1.1 No other devices seem to have an issue. What is the most probable cause of the problem?

The wrong default gateway address has been configured.

You have a small network as shown. The user on workstation A reports that he cannot communicate with remote workstation E. You begin to troubleshoot the problem by sending a ping from workstation A to remote workstation E, but you cannot reach this host. Next, you try sending pings from workstation A to the remote workstations C and D, and you cannot reach either of them. You also try pinging the IP address assigned to interface 1 on the Default Gateway router, which is also unsuccessful. Finally, you ping workstation B, and this time, you get a successful reply. Which of the following can you assume based on these results?

There is a problem with the default gateway router.

If you have one router on your network and the IP address doesn't match one of the devices on your network, where would the default static route direct packets?

To your Internet Service Provider

Which feature implemented with a Distance Vector Routing Protocol reduces the convergence time?

Triggered updates

Match each route types with its description.

Used to minimize the number of routing table entries. Sum : Summary static route Works best when only one path exists to a part of the network. : Default static route Used when connecting to a remote network. : Standard static route Is a backup route. : Floating static route

Which of the following commands lists a workstation's ARP cache?

arp -a

You have a small network as shown. You have configured RIP on both RouterA and RouterB. The show ip route command on RouterA shows the following information: Codes: C - connected, S - static, R - RIP, M - mobile, B - BGPD - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter areaN1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2E1 - OSPF external type 1, E2 - OSPF external type 2i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2ia - IS-IS inter area, * - candidate default, U - per-user static routeo - ODR, P - periodic downloaded static route Gateway of last resort is not set R 10.0.0.0/8 [120/1] via 192.168.4.14, 00:00:02, Serial0/1/0C 192.168.1.0/24 is directly connected, FastEthernet0/0192.168.4.0/30 is subnetted, 1 subnetsC 192.168.4.12 is directly connected, Serial0/1/0 You want to configure a default route so that all packets for unknown networks are sent to RouterB. Which command should you use?

ip default-network 10.0.0.0

You have a small network as shown. You want to configure a route so that packets sent to any non-directly connected network get sent to RouterB. Which command would you use?

ip route 0.0.0.0 0.0.0.0 192.168.4.14

You need to configure a static route on your Cisco router. The destination network is 192.65.178.0 with a subnet mask of 255.255.255.0. The default gateway is 192.65.179.1, and the IP address of the destination host for the message is 192.65.178.15. Which of the following commands configures this route?

ip route 192.65.178.0 255.255.255.0 192.65.179.1

Which of the following utilities gives you the most information about the operational status of a router?

telnet