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Answers and Explanations

  1. Answers: A and B. You can issue show or debug commands in either User EXEC or Privileged mode. C is incorrect, as you cannot use show commands while in Line Configuration mode. D is incorrect, as you cannot use show commands while in Global Configuration mode.

  2. Answers: A and B. You can store Cisco device configurations on FTP and TFTP servers. TFTP is preferred because of its lower overhead. C is incorrect, as SQL databases do not store Cisco device configurations. D is incorrect, as Oracle databases are not used to store Cisco device configurations.

  3. Answer: D. The show interface command gives you all the physical and logical configuration information about a particular interface. A is incorrect, as ping is a TCP/IP utility that allows you to "ping" a connection to see whether there is connectivity. B is incorrect, as this is the command you use on a Microsoft Windows PC to find your IP address. C is incorrect, as the traceroute command allows you to track the packet’s path to its destination.

  4. Answer: C. You type enable to enter Privileged EXEC mode. A is incorrect, as it is not a valid command. B is incorrect, as it is not a valid command. D is incorrect, as this command takes you out of Privileged EXEC mode.

  5. Answer: A. The Catalyst switches have default configurations set up so that they can perform their basic switching roles (which provides separate collision domains for the attached devices) without any further configurations. B is incorrect, as setting up an IP address assists you in remote management via Telnet, but isn’t required. C is incorrect because VLANs create separate broadcast domains, not collision domains. D is incorrect, as the Cisco IOS is not required for switches to function. In fact, some low-end Catalyst switches do not have the IOS running.

  6. Answer: B. The prompt Router# indicates the router is in Privileged EXEC mode. A is incorrect, as this prompt indicates that you are in User EXEC mode. C is incorrect, as this is not a valid prompt. D is incorrect, as this is not a valid prompt.

  7. Answer: B. The > tells you that you are in User EXEC mode. A is incorrect, as you are not in Privileged EXEC mode. C is incorrect, as you can have the User EXEC mode prompt without configuring anything. D is incorrect, as the > prompt does not indicate any hardware failures.

  8. Answer: C. The hostname command assigns a name to your device. A is incorrect, as enable gets you into Privileged EXEC mode on the switch. B is incorrect, as the hostname command is one word, not two. D is incorrect, as this is not a valid command.

  9. Answer: D. You must place the Management IP address on the Management VLAN, which is VLAN 1, by default. A and B are incorrect because you cannot configure IP address settings while in Privileged mode. Answer C is incorrect. Although this syntax was used to assign an IP address to a Catalyst 1900 switch, this series of switch has long since been discontinued from Cisco’s product line.

  10. Answer: C. The command clock ? gives you all the parameters (syntax) that follow after the Clock main command. A is incorrect, as cl? simply tells you what commands start with cl. B is incorrect, as the IOS attempts to clarify all commands that start with clock, which is the actual command here. D is incorrect because you get an invalid command error message.

  11. Answer: B. The command banner motd [delimiting character] is what sets up a displayed message when you log in to a router. In this case, you use the command banner motd &, indicating that you will use the & sign to signal the end of your logon banner. A is incorrect, as the command is banner motd. C is incorrect, as you must issue the command in Global Configuration mode, not Privileged mode. D is incorrect, as that is an invalid command.

  12. Answers: A, C, and D. You can telnet into a Cisco router if you know the IP address of one of the interfaces or the name of the router with DNS running. You can connect with a rollover cable to the Console port. You can also dial in via modem through an AUX port. B is incorrect, as FTP merely allows you to download a configuration.

  13. Answer: C. The console password requires anyone who attempts to plug a rollover serial cable into the console port to provide a password to log on. A is incorrect, as a vty is a virtual port or Telnet port. B is incorrect, as there are no interface passwords. D is incorrect, as the Enable password prevents unauthorized users from entering privileged mode.

  14. Answer: D. You probably have the baud rate set too low or too high. The baud rate for your PC’s COM port needs to be configured at 9600bps. A is incorrect, as you must use an RJ-45 rollover cable. You cannot change the connectors. B is incorrect, as you will more than likely encounter the same issue with any other terminal program. C is incorrect, as you rarely, if ever, need to restart the router to fix a problem.

  15. Answer: A. The show running-config command shows you all currently running configurations in RAM. B is incorrect, as you would see similar output; however, this shows the Current configuration. C is incorrect, as that command shows you the routing table on your router. D is incorrect, as the show version command gives you the up-to-date information on which IOS you are running, as well as the configuration register settings.

  16. Answer: B. You give the East router the username of the router to which you want to authenticate. In this case, it would be West. A is incorrect, as East would be the hostname of the router, not the username. C and D are incorrect, as neither one of these routers is mentioned as a possible connection. If there were routers named North and South, the East router would need usernames for both of them.

  17. Answer: C. High-level Data Link Control (HDLC) is the default serial encapsulation on Cisco routers. A is incorrect, as you must configure your Cisco router for PPP. B is incorrect, as you must specify SLIP as an encapsulation. D is incorrect, as ATM is ordered through a service provider and is not the default encapsulation.

  18. Answer: C. Challenge Handshake Authentication Protocol (CHAP) requires a three-way handshake. It requires a challenge, reply, and Accept/Reject response. A is incorrect, as there are no one-way authentications. B is incorrect, as CHAP has three-way, and Password Authentication Protocol (PAP) uses a two-way handshake. D is incorrect, as all authentication protocols need mutual agreement.

  19. Answer: B. Cisco routers do not display any console messages or debug output to the vty ports (Telnet sessions) by default. To enable this feature, you need to type terminal monitor from the standard Privileged EXEC mode prompt. Answer A is incorrect because there is a debug ip packet command. Answer C is incorrect because the debug command shows every single packet going through your router, not just the troubled interfaces. D is incorrect, as you can enable debug commands through any access method that allows you to reach a Privileged EXEC mode prompt.

  20. Answer: A. This output is generated by the show version command. It gives you the current version of the IOS that is running, as well as other information about the router. B is incorrect, as this does not show the currently running configuration. C is incorrect, as this does not show the configuration that is saved in NVRAM. D is incorrect, as there is no such command.

  21. Answer: D. The show ip interface brief command gives you a summary of all interfaces on the router. This is a good command to use to identify any issues with your interface’s connectivity. A is incorrect, as this gives you detailed information on interface Ethernet 0/0. B is incorrect, as this is not a valid command. C is incorrect, as this command gives you detailed information about serial interface 0/1.

  22. Answer: D. Notice that one router is running HDLC while the other is running PPP. They are not able to communicate. A is incorrect, as both have addresses that are on the appropriate network. B is incorrect, as routers that are directly connected do not need a routing protocol to communicate. C is incorrect, as you notice that on both routers, the lines are "up," which means that there is electrical connectivity (Layer 1).

  23. Answers: A and B. You can copy your running-config to NVRAM (startup-config) and to the flash memory (if there is room). C is incorrect, as correct syntax for a copy command is source to destination. Because you are copying from your running-config, that is the source, not the destination. D is incorrect, as the Cisco router does not allow you to transfer your configuration using the HTTP protocol.

  24. Answers: A, D, and E. Frame relay, Point-to-Point Protocol (PPP), and HDLC are all WAN encapsulation protocols. B is incorrect, as Ethernet is a LAN encapsulation. C is incorrect, as token ring is a LAN encapsulation, as well.

  25. Answer: B. The command service password-encryption encrypts all of the system passwords that are set. A is incorrect, as you cannot issue this command at the Privileged EXEC mode prompt. It must be done in Global Configuration mode. C is incorrect, as this command does not work in Privileged EXEC mode and does not encrypt all of the passwords. D is incorrect, as this command gives you only an encrypted Privileged EXEC mode password, not all of the system passwords.

  26. Answer: D. You must first go to the vty line where you want to put the password and then use the password command. You finish by specifying that users must log in with the password by using the login command. A is incorrect, as it is the correct method to configure a password on the console interface, not Telnet. B is incorrect, as the second command typed is invalid. C is incorrect, as the command for the password is incorrect. You do not use the enable secret command here.

  27. Answer: A. The clockrate command sets the clocking, or physical speed of the interface. It establishes the DCE side of a serial connection. It acts as sort of a metronome that specifies the timing of sending data. Because the service provider is typically the clock rate source, this command is primarily used in lab environments to emulate a service provider connection. B is incorrect, as keepalives are sent on Ethernet interfaces. C is incorrect, as the advertised bandwidth of an interface is set with the bandwidth command. D is incorrect, as you use the Clock command to set the time on your router, or you can have it set to receive its time from an NNTP server.

  28. Answer: D. There are five vty (Telnet) lines established by default on a Cisco router. They start at vty 0. A is incorrect, as this is an invalid command. B is incorrect, as this allows you to configure your Ethernet interface, not Telnet lines. C is incorrect, as the numbering of the vty lines starts at 0, not 1.

  29. Answers: A and D. You can issue show commands from User EXEC mode (>) or Privileged EXEC mode (#). B is incorrect, as you cannot issue show commands from Global Configuration mode. C is incorrect, as you cannot issue show commands from Route Protocol mode. E is incorrect, as ROMON mode, or RomMonitor, is a low-level maintenance utility that helps bring back a corrupted router’s IOS image.

  30. Answer: B. Older versions of the IOS do not support encrypted Privileged EXEC mode passwords. By placing an Enable password, you still have a way to keep people out of Privileged EXEC mode if reverting to an older IOS. A is incorrect, as applications do not use Privileged EXEC mode passwords to access a Cisco router. C is incorrect, as the router ignores the Enable password after the Enable Secret password is configured. D is incorrect, as you type the Enable Secret password only to access Privileged EXEC mode.

  31. Answer: C. The keyboard shortcut Ctrl+Z brings you back to Privileged EXEC mode. A is incorrect, as this is the method to suspend a Telnet session. B is incorrect, as this is one of the ways to stop a process from running. D is incorrect, as this merely moves you back one mode. In this case, you merely go back to Global Configuration mode.

  32. Answers: A, B, and E. The Network Control Protocols (NCPs) are negotiated for the Layer 3 protocols in use on the WAN, such as IPXCP for IPX/SPX, IPCP for TCP/IP, and other Layer 3 protocols. CHAP authentication and Multilink Protocol are options that can also be negotiated during the LCP portion. C is incorrect, as UDP is a Layer 4 protocol, and PPP does not work at Layer 4. D is incorrect, as Q.931 is a signaling standard used by ISDN.

  33. Answer: D. Reloading the router forces the router to reboot and load the configuration in the router’s NVRAM. A is incorrect, as this places you into the router configuration setup script. B is incorrect, as this copies your currently running configuration into NVRAM. C is incorrect, as this merely "merges" the saved configuration with the currently running configuration. If changes made to the running configuration were not addressed in your saved configuration, they remain and are not overwritten.

  34. Answer: A. Ctrl+P is used in place of the up arrow on the keyboard for older terminal programs. Ctrl+A is used to move to the beginning of the command line. Answer B is incorrect, as there is no Ctrl+L command and Ctrl+B moves back a character. Answer C is incorrect because Ctrl+D deletes the character under the curser. Ctrl+E moves the cursor to the end of the command line, making D incorrect.

  35. Answer: B. The correct baud rate is 9600; thus, B is the correct answer. A, C, and D are incorrect baud rate settings and cause your screen to incorrectly display information from your console port.

  36. Answer: A. You must have an IP address configured on an interface for a router or on a Management VLAN for a Catalyst switch. B is incorrect, as Simple Network Management Protocol (SNMP) is not required for Telnet. C is incorrect, as Cisco Discovery Protocol (CDP) is not required for Telnet to work. D is incorrect, as Cisco Devices have five vty ports configured by default.

  37. Answer: D. The disable command takes you from Privileged EXEC mode back to User EXEC mode. A is incorrect, as this is the command that takes you from User EXEC mode to Privileged EXEC mode. B is incorrect, as this logs you out of your connection. C is incorrect, as this command places you in Global Configuration mode.

  38. Answer: D. You must be in vlan configuration mode for VLAN1. A is incorrect because you cannot configure IP addresses in Privileged EXEC mode. B is incorrect because that is not a correct command. C is incorrect because you must specify the subnet mask when performing this command.

  39. Answer: B. The show flash command gives you the contents of the flash memory, as well as the amount of remaining memory. A is incorrect, as this command shows all the configurations stored in NVRAM. C is incorrect, as this is not a valid command. D is incorrect, as show version gives you the currently running IOS image and information about the router, such as uptime and configuration register settings.

  40. Answer: D. You use the show interface vlan command to verify the IP address on that switch. A is incorrect because the show ip command is no longer used on the Catalyst switch series. B is incorrect because this merely gives you information on what ports belong to a VLAN. C is incorrect because this command shows you the routing table on the switch, if the switch has Layer 3 capabilities.

  41. Answer: C. You are taken to the System Configuration dialog if there are no configurations saved in NVRAM. A is incorrect, as you are taken to ROMON mode if the IOS is corrupted. B is incorrect, as missing parameters do not start the System Configuration dialog. D is incorrect, as the question stated that you saw the output after powering up the router. You can get this text if you issue that command, but that would have happened after you had logged in.

  42. Answer: A. The command show con does not have enough characters for the IOS to finish it. B is incorrect, as you see the incomplete command output. C is incorrect, as this produces the unknown command output. D is incorrect, as context-sensitive help requires the use of the ?.

  43. Answer: C. The dollar sign ($) indicates that there is text to the left of the symbol. A is incorrect, as the (^) symbol typically indicates where a command has erred. B is incorrect, as commands longer than one line are allowed. D is incorrect, as the router does not shorten any commands unless you have typed in a shortened version, such as config t for configure terminal.

  44. Answer: D. The history size command permanently alters the command history buffer. A is incorrect, as this command adjusts the buffer only for the current session. B is incorrect, as you cannot issue the history size command from Privileged EXEC mode. C is incorrect, as you do not issue the terminal history command from Global Configuration mode, and it is the wrong command as well.

  45. Answers: A and C. You can view the descriptions placed on the interfaces with the show interfaces command or show running-config. B is incorrect, as the show flash command shows the IOS images and any configurations saved to flash memory. D is incorrect, as this command gives you all the running routing protocols, such as RIP or IGRP.

  46. Answer: B. The logging synchronous command enables the IOS to retype your input after displaying a console message. This does not interrupt your command. A is incorrect, as exec-timeout sets how long a session can remain idle without logging off the user. C is incorrect, as this command merely brings you to Line Configuration mode. D is incorrect, as this is an invalid command.

  47. 47 Answer: D. This is the command issued on a 7000 or 7500 Cisco router with a VIP card. It has a slot, port adapter, and port number. A, B, and C are incorrect definitions.

  48. Answer: D. You issue the clockrate command in Interface Configuration mode, and it must be set in bits per second. A and B are incorrect, as the bandwidth command is good only for the advertised bandwidth. C is incorrect, as you must specify the speed in bits per second, not Kbps.

  49. Answer: A. You use the encapsulation command in Interface Configuration mode—for example, router1(config-if)#encapsulation frame-relay. B is incorrect, as you issue the command in Interface Configuration mode. C is incorrect, as you can issue limited show commands only in User mode. D is incorrect, as you can enter configuration modes and perform router maintenance.

  50. Answer: B. All your passwords are shown in encrypted form after issuing the service password-encryption command. The passwords encrypted are identified as password type 7. A is incorrect, as the encrypted passwords are shown in a hashed format. C is incorrect, as the rest of the output looks correct. D is incorrect, as the enable secret command gives you an encrypted Privileged EXEC mode password, which is identified as password type 5.

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