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This Practice Test provides you with questions related to the IOS CLI Router objective in the "Cisco Basics, IOS & Network Basics" category. This question set also contains questions on the Telnet objective, which is part of the "Network Management" subject category. Because the CCNA exam is in a multiple choice format, these questions, while related to hands-on router commands, are formatted as they would be for the actual test.

  1. Which is the global configuration command to enable CDP on a router where it has been disabled?

    1. CDP enable

    2. show CDP

    3. CDP run

    4. run CDP

    Answer A is incorrect; enable is not part of the command syntax for enabling CDP on the router. Answer B is incorrect; show CDP is a fragment of an actual command that, with additional parameters, would enable you to view various CDP parameters related to the router. Answer C is correct; CDP run, executed at the configuration prompt, enables CDP on the router. Answer D is incorrect; the command words are reversed, providing an incorrect command syntax.

  2. Which prompt shows you are in the privileged mode?

    1. router>

    2. router (config)

    3. router#

    4. router (config-if)

    Answer A is incorrect; this shows the router in the user mode. Answer B is incorrect; this shows a router in the global configuration mode. Answer C is correct; it is the privileged prompt that is shown. Answer D is incorrect; this shows a router in the interface configuration mode.

  3. What are possible avenues for logging in to a router (select all that apply)?

    1. A virtual terminal

    2. The router console

    3. An auxiliary connection through a modem

    4. Configuration session

    Answer A is correct; you can telnet to a router using a virtual terminal connection. Answer B is correct; you can directly log in to a router through a router console connection. Answer C is correct; an auxiliary connection through a modem enables you to log in to a router remotely. Answer D is incorrect; you must be logged in to the router before entering a configuration session from the privileged mode.

  4. To get help with the parameters, what you should enter directly after a specific router command at the CLI?

    1. Type the command and follow it with a question mark.

    2. Type help and view the command parameters on the help screen.

    3. Type the command, press the spacebar, and type a question mark.

    4. Type a question mark at any prompt.

    Answer A is incorrect; this will work only in cases where you want to find the complete command word when a partial command has been typed in. Answer B is incorrect; the help command provides assistance with only how to use help on the router. Answer C is correct; you must complete a portion of the command (in other words, a whole command word) and then follow it by a space to view additional parameters that follow that command. Answer D is incorrect; this will show a list of all the commands available at the current prompt.

  5. To view the CDP information for a particular interface type such as Ethernet 0, you would use the command:

    1. show interface

    2. sh cdp int e0

    3. show cdp interface

    4. show cdp neighbor

    Answer A is incorrect; this command will provide only interface settings and activity on the interface. Answer B is correct; the show cdp int command followed by a particular interface (such as e0) provides CDP information on that specified interface. Answer C is incorrect; this will show the cdp information for all CDP-enabled interfaces on the router. Answer D is incorrect; the show cdp neighbor command provides a listing of CDP neighbors for the router.

  6. To view the contents of NVRAM use the command:

    1. show run-config

    2. show flash

    3. show startup-config

    4. show mem

    Answer A is incorrect; this command shows the currently running configuration held in RAM. Answer B is incorrect; this shows the IOS image files held in FLASH RAM. Answer C is correct; the show startup-configuration command shows the startup configuration stored in NVRAM. Answer D is incorrect; the show mem command provides a listing of the items currently held in various memory levels of RAM.

  7. Which memory type holds the full IOS image for the router?

    1. ROM

    2. RAM

    3. NVRAM

    4. Flash

    Answer A is incorrect; ROM holds the bootstrap program and will hold a truncated version of the IOS image (except on the 7000 series routers, where it is a full IOS image). Answer B is incorrect; RAM is used to load portions of the IOS into memory. Answer C is incorrect; NVRAM is used to hold configuration files. Answer D is correct; the IOS image is typically held and loaded from Flash RAM.

  8. Which command enables you to view recently used commands?

    1. sh history

    2. set history

    3. sh protocol

    4. sh run-config

    Answer A is correct; the show history command enables you to see the last 10 CLI commands (by default). Answer B is incorrect; this command is used to set the size of the history file (the number of commands remembered). Answer C is incorrect; show protocol is used to view protocol information related to the router. Answer D is incorrect; the show run command provides the running configuration contained in RAM.

  9. Which command provides information about other directly connected routers?

    1. show ip route

    2. show cdp neighbor

    3. show protocol

    4. sh interface

    Answer A is incorrect; this command provides the IP routing table. Answer B is correct; show cdp neighbor provides information on routers directly connected to the router. Answer C is incorrect; show protocol provides a listing of the protocols being routed on the router. Answer D is incorrect; show interface provides interface settings for the router's various interfaces.

  10. How do you move the cursor to the beginning of the command line after you've typed a command?

    1. Ctrl+B

    2. Home

    3. Ctrl+F

    4. Ctrl+A

    Answer A is incorrect; these keys enable you to move one character back. Answer B is incorrect; this keystroke will have no result at the CLI. Answer C is incorrect; this key sequence moves forward one character. Answer D is correct; use Ctrl+A to move the cursor to the beginning of a typed command on the command-line interface.

Cheat Sheet

The following are connections to a router:

  • Console port

  • Auxiliary port via a modem or other device

  • Telnet over the network from another device

The router provides several CLI modes:




Basic examination of the router status; limited command set; cannot change configuration.


Greater examination of router status and configuration; capability to change router status and enter configuration mode.


Enables configuration of global router parameters and the entering of specific configuration information for router interfaces and other settings.


The ROM monitor mode; enables recovery of router functions when the IOS image can't be found (such as a corrupt IOS image). This mode can also be entered by pressing the Break key on a router console during the first minute of the system bootup (this mode can be used to help recall lost passwords on the router).


This mode is initiated on a new router or a router that does not have a valid startup configuration. It walks you through the router configuration in the System dialog box.

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