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Keyboard help in the router CLI

Keyboard help in the router CLI
2.2.6 This page will introduce some router help functions.


A question mark, ?, can be entered at the user EXEC or privileged EXEC mode prompt to display a list of available commands. Notice the --More-- at the bottom of the display in Figure . The --More-- prompt indicates that there are multiple screens of output. When a --More-- prompt appears, press the Spacebar to view the next available screen. To display just the next line, press the Return or Enter key. Press any other key to return to the prompt.

To access privileged EXEC mode, type enable or the abbreviation en or ena. This might cause the router to prompt the user for a password if one has been set. Figure lists the commands that are available in privileged EXEC mode.

Screen output varies, depending on Cisco IOS software level and router configuration.

The help function, or question mark, ?, can be used to display the commands that are used to perform certain tasks. The following exercise illustrates one of the many uses of the help function.

If a user wants to set the router clock and does not know the command, the help function can be used as follows:

1. Use ? to find the command for setting the clock. The help output shows that the clock command is required.

2. Check the syntax for changing the time.

3. Enter the current time by using hours, minutes, and seconds, as shown in Figure . The system indicates that additional information needs to be provided to complete the command.

4. Press Ctrl-P or the Up Arrow to repeat the previous command entry. Then add a space and a question mark (?) to reveal the additional arguments. Now the command entry can be completed.

5. The caret symbol (^) and help response indicate an error. The placement of the caret symbol shows where the possible problem is located. To input the correct syntax, re-enter the command up to the point where the caret symbol is located and then enter a question mark (?).

6. Enter the year, using the correct syntax, and press Return or Enter to execute the command.

As demonstrated in the IOS Auto-Completion e-Lab, typing an abbreviated command, such as sh, followed by the Tab key completes a partial command name.

The next page will introduce some enhanced editing commands that are available in the Cisco IOS.

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