Shortcuts for Entering Commands

To enhance efficiency, Cisco IOS Software has some shortcuts for entering commands. Although these are great to use in the real world, when it comes time to take the CCNA 200-301 exam, make sure you know the full commands, not just the shortcuts.

Using the Key to Complete Commands

When you are entering a command, you can use the key to complete the command. Enter the first few characters of a command and press the key. If the characters are unique to the command, the rest of the command is entered in for you. This is helpful if you are unsure about the spelling of a command.

Router# sh = Router# show

Console Error Messages

You may see three types of console error messages when working in the CLI:

• Ambiguous command

• Incomplete command

• Invalid input

Using the Question Mark for Help

The following output shows you how using the question mark can help you work through a command and all its parameters.

Router# ?	Lists all commands available in the current command mode
Router# c? calendar call-home cd clear clock cns configure connect copy crypto	Lists all the possible choices that start with the letter c
Router# cl? clear clock	Lists all the possible choices that start with the letters cl
Router# clock % Incomplete Command	Tells you that more parameters need to be entered
Router# clock ? read-calendar set update-calendar	Shows all subcommands for this command
Router# clock set 19:50:00 14 July 2019 ?	Pressing the key confirms the time and date configured
Router#	No Error message/Incomplete command message means the command was entered successfully

enable Command

exit Command

end Command

disable Command

logout Command

Setup Mode

Setup mode starts automatically if there is no startup configuration present.

Keyboard Help

The keystrokes in the following table are meant to help you edit the configuration. Because you’ll want to perform certain tasks again and again, Cisco IOS Software provides certain keystroke combinations to help make the process more efficient.

^ Router# confog t            ^ % Invalid input detected at '^' marker. Router# config t Router(config)#	Shows you where you made a mistake in entering a command
	Indicates that the line has been scrolled to left
	Moves cursor to beginning of line
	Moves cursor back one word
	Moves cursor back one character
	Moves cursor to end of line
	Moves cursor forward one character
	Moves cursor forward one word
	Allows the user to interrupt an IOS process such as ping or traceroute
	Moves you from any prompt back down to privileged EXEC mode. Can also be used to interrupt the output being displayed and return to privileged EXEC mode
	Deletes the word to the left of the cursor
	Deletes the entire line
	Swaps or transposes the current character with the one before it
	Erases characters from the cursor to the end of the line
	Erases characters from the cursor to the beginning of the line
	Deletes from cursor to the end of the word
	Removes characters to the right of the cursor
	Removes characters to the left of the cursor
	Reprints the line
	Refreshes the line—use this if the system sends a message to the screen while a command is being entered and you are not using line synchronization. This brings your command to the next line without the message interfering with the command
	Exits from global configuration mode and moves you to privileged EXEC mode
	Makes the letter at the cursor uppercase
	Makes the letter at the cursor lowercase
	Makes the letters from the cursor to the end of the word uppercase
Router# terminal no editing Router#	Turns off the ability to use the previous keyboard shortcuts
Router# terminal editing Router#	Reenables enhanced editing mode (can use previous keyboard shortcuts)

History Commands

	Recalls commands in the history buffer in a backward sequence, beginning with the most recent command
	Returns to more recent commands in the history buffer after recalling commands with the key sequence

terminal Commands

Be careful when you set the size to something larger than the default. By telling the router to keep the last 256 commands in a buffer, you are taking memory away from other parts of the router. What would you rather have: a router that remembers what you last typed in or a router that routes as efficiently as possible?

show Commands

Using the Pipe Parameter ( | ) with the show or more Commands

By using a pipe (|) character in conjunction with a show command or a more command, you can set filters for specific information that you are interested in.

Router# show running-config | section gig0/0

Using the no and default Forms of Commands

Almost every configuration command has a no form. In general, use the no form to disable a feature or function. Use the command without the no keyword to reenable a disabled feature or to enable a feature that is disabled by default.

Many CLI commands also have a default form. By issuing the default command-name command, you can configure the command to its default setting. The Cisco IOS Software command reference documents located on Cisco.com describe the function of the default form of the command when it performs a different function from either the plain form or the no form of the command. To see what default commands are available on your system, enter default ? in the appropriate command mode: