Cisco CCNA Cisco Certified Network Associate CCNA (803)

Transcription

1 1 Cisco CCNA Cisco Certified Network Associate CCNA (803) QUESTION: 1 Refer to the exhibit. The network shown in the exhibit has just been installed. Host B can access the Internet, but it is unable to ping host C. What is the problem with this configuration? A. The switch port connected to the router is incorrectly configured as an access port. B. The switch port that sends VLAN 13 frames from the switch to the router is shut down. C. Host B should be in VLAN 13. D. The gateway for host B is in a different subnet than the host is on. E. The address of host C is incorrect. Answer: E The Fa0/0.13 interface of the router is the subinterface used for VLAN 13. The IP address of this interface is , so all devices in VLAN 13 will have their default gateway set to this which means that all devices in VLAN13 need to be in the /24 subnet. As can be seen in the output above, Host C is in VLAN 13 but its IP address has been incorrectly configured for the /24 subnet. QUESTION: 2 A network administrator needs to connect the main bank office to two branch offices. During business hours, the bank requires a redundant connection to maintain connectivity between the branch offices and the main bank. The primary connection to the branch offices should be cost effective and provide at least 512 kbps dedicated access to the branch offices. The backup connection should only be used when the primary connection goes down. Also, the backup

2 2 connection should have a relatively short setup time, and provide 128 kbps of bandwidth. Which combination of technologies meets these requirements? A. primary connection - Frame Relaybackup connection - ISDN B. primary connection - ATMbackup connection - Frame Relay C. primary connection - Frame Relaybackup connection - dialup D. primary connection - dedicated leased linebackup connection - ISDN Answer: A QUESTION: 3 What does the "Inside Global" address represent in the configuration of NAT? A. the MAC address of the router used by inside hosts to connect to the Internet B. a globally unique, private IP address assigned to a host on the inside network C. the summarized address for all of the internal subnetted addresses D. a registered address that represents an inside host to an outside network Answer: D With NAT, Cisco defines 4 different types of addresses as follows: Inside local address - The IP address assigned to a host on the inside network. This is the address configured as a parameter of the computer's OS or received via dynamic address allocation protocols such as DHCP. The address is likely not a legitimate IP address assigned by the Network Information Center (NIC) or service provider. Inside global address - A legitimate IP address assigned by the NIC or service provider that represents one or more inside local IP addresses to the outside world. Outside local address - The IP address of an outside host as it appears to the inside network. Not necessarily a legitimate address, it is allocated from an address space routable on the inside. Outside global address - The IP address assigned to a host on the outside network by the host's owner. The address is allocated from a globally routable address or network space. The above definitions still leave a lot to be interpreted. For this example, this document redefines these terms by first defining "local address" and "global address." Keep in mind that the terms "inside" and "outside" are NAT definitions. Interfaces on a NAT router are defined as "inside" or "outside" with the NAT configuration commands, ip nat inside and ip nat outside. Networks to which these interfaces connect can then be thought of as "inside" networks or "outside" networks, respectively. Local address - A local address is any address that appears on the "inside" portion of the network. Global address - A global address is any address that appears on the "outside" portion of the network. QUESTION: 4

3 3 When a new trunk is configured on a 2950 switch, which VLANs by default are allowed over the trunk link? A. all VLANs B. only VLANs 1-64 C. only the VLANs that are specified when creating the trunk D. no VLANs Answer: A QUESTION: 5 Refer to the exhibit. What can be concluded from the output of the debug command? A. A router is connected to interface Serial0/3 of the Border router. The OSPF router ID of the connected router is the IP address of the connected interface. B. The output represents normal OSPF operation. C. The OSPF router connected to interface Serial0/1 has NOT formed a neighbor relationship with the Border router. D. The interfaces of two OSPF routers connected to the Border router are in the same subnet. Answer: C This debug ip ospf events output shown might appear if any of the following situations occurs: 1. The IP subnet masks for routers on the same network do not match. 2. The OSPF hello interval for the router does not match that configured for a neighbor. 3. The OSPF dead interval for the router does not match that configured for a neighbor. If a router configured for OSPF routing is not seeing an OSPF neighbor on an attached network, perform the following tasks: 1. Make sure that both routers have been configured with the same IP mask, OSPF hello interval, and OSPF dead interval. 2. Make sure that both neighbors are part of the same area type. QUESTION: 6 Why has the network shown in the exhibit failed to converge?

4 4 A. The autonomous system number has not been properly configured. B. The network numbers have not been properly configured on the routers. C. The no auto-summary command needs to be applied to the routers. D. The bandwidth values have not been properly configured on the serial interfaces. E. The subnet masks for the network numbers have not been properly configured. Answer: C To restore the default behavior of automatic summarization of subnet routes into network-level routes, use the auto-summary command in router configuration mode. To disable this function and transmit subprefix routing information across classful network boundaries, use the no form of this command. Without disabling auto summarization, each router will advertise the /24 route, and the specific /26 networks will not be known. QUESTION: 7 What is a global command? A. a command that is set once and affects the entire router B. a command that is implemented in all foreign and domestic IOS versions C. a command that is universal in application and supports all protocols D. a command that is available in every release of IOS, regardless of the version or deployment status E. a command that can be entered in any configuration mode Answer: A When you enter global configuration mode and enter a command, it is applied to the running configuration file that is currently running in ram. The configuration of a global command affects the entire router. An example of a global command is one used for the hostname of the router. Incorrect Answers:

5 5 Global configuration commands must be performed while in global configuration mode. For example, when you are in the interface configuration mode, you most likely will need to exit out into global mode to type in the commands. Global commands do not necessarily support every protocol. This is not necessarily true, since there are certain global commands that are supported on one feature set that are not on a different feature set of IOS. Global commands can become outdated, and can be replaced by newer commands in the newer releases of IOS. QUESTION: 8 Which IP addressing scheme would be correct for the topology shown in the graphic? A. Host /24; Host /24; Host /24 B. Host /24; Host /24; Host /24 C. Host /24; Host /24; Host /24 D. Host /24; Host /24; Host /24 Answer: D QUESTION: 9 The network administrator needs to address seven LANs. RIP version 1 is the only routing protocol in use on the network and subnet 0 is not being used. What is the maximum number of usable IP addresses that can be supported on each LAN if the organization is using one class C address block? A. 8 B. 6 C. 30 D. 32

6 6 E. 14 F. 16 Answer: C QUESTION: 10 In a switched environment, what does the IEEE 802.1Q standard describe? A. the operation of VTP B. a method of VLAN trunking C. an approach to wireless LAN communication D. the process for root bridge selection E. VLAN pruning Answer: B A broadcast domain must sometimes exist on more than one switch in the network. To accomplish this, one switch must send frames to another switch and indicate which VLAN a particular frame belongs to. On Cisco switches, a trunk link is created to accomplish this VLAN identification. ISL and IEEE 802.1Q are different methods of putting a VLAN identifier in a Layer 2 frame. The IEEE 802.1Q protocol interconnects VLANs between multiple switches, routers, and servers. With 802.1Q, a network administrator can define a VLAN topology to span multiple physical devices. Cisco switches support IEEE 802.1Q for FastEthernet and Gigabit Ethernet interfaces. An 802.1Q trunk link provides VLAN identification by adding a 4-byte tag to an Ethernet Frame as it leaves a trunk port. QUESTION: 11 Which two benefits can be obtained by using VTP in a switching environment? (Choose two.) A. Allowing frames from multiple VLANs to use a single interface. B. Allowing switches to read frame tags. C. Maintaining VLAN consistency across a switched network. D. Allowing VLAN information to be automatically propagated throughout the switching environment. E. It allows ports to be assigned to VLANs automatically. Answer: C, D VTP minimizes the possible configuration inconsistencies that arise when changes are made. These inconsistencies can result in security violations, because VLANs can crossconnect when duplicate names are used. They also could become internally disconnected when they are mapped from one LAN type to another, for example, Ethernet to ATM LANE ELANs or FDDI

7 VLANs. VTP provides a mapping scheme that enables seamless trunking within a network employing mixed-media technologies. VTP provides the following benefits: VLAN configuration consistency across the network Mapping scheme that allows a VLAN to be trunked over mixed media Accurate tracking and monitoring of VLANs Dynamic reporting of added VLANs across the network Plug-and-play configuration when adding new VLANs QUESTION: 12 Which two statements are true about the command ip route ? (Choose two.) A. It establishes a static route to the network. B. It configures the router to send any traffic for an unknown destination to the network. C. It creates a static route to the network. D. It uses the default administrative distance. E. It configures the router to send any traffic for an unknown destination out the interface with the address F. It is a route that would be used last if other routes to the same destination exist. Answer: A, D This question is to examine the static route-related concept. ip route This is a static route configuration command is the destination network, is the next hop. The administrative distance is not configured, so the default administrative distance is used. The correct answers are A and D. QUESTION: 13 Which two of the following are advantages of Layer 2 Ethernet switches over hubs? (Choose two.) A. To increase the size of broadcast domains B. To filter frames according to MAC addresses C. To allow simultaneous frame transmissions D. To increase the maximum length of UTP cabling between devices E. decreasing the number of collision domains F. increasing the size of broadcast domains Answer: B, C

8 8 QUESTION: 14 Refer to the exhibit. A network associate needs to configure the switches and router in the graphic so that the hosts in VLAN3 and VLAN4 can communicate with the enterprise server in VLAN2. Which two Ethernet segments would need to be configured as trunk links? (Choose two.) A. A B. B C. C D. D E. E F. F Answer: C, F Layer 3 routing is needed to implement communication between VLANs, so a trunk link is configured between Router and Switch2. Both Switch1 and Switch2own VLAN3 and VLAN4 members, so a trunk link is configured between Switch1 and Switch2. QUESTION: 15 Which two values are used by Spanning Tree Protocol to elect a root bridge? (Choose two.) A. bridge priority B. IP address C. MAC address D. IOS version E. amount of RAM F. speed of the links Answer: A, C Two values are compared to elect a root bridge in STP: bridge priority and MAC address. Switch having lowest bridge ID will become the root bridge. The bridge ID is how STP keeps track of all the switches in the network. It is determined by a combination of the bridge priority

9 9 (32, 768 by default on all Cisco switches) and the base MAC address. The bridge with the lowest bridge ID becomes the root bridge in the network.