2.2 Starting a Router  
  2.2.6 Keyboard help in the router CLI  
Typing a question mark (?) at the user EXEC mode prompt or the privileged EXEC mode prompt displays a handy list of available commands. Notice the "--More--" at the bottom of the sample display. The screen displays many lines at one time. The "--More--" prompt at the bottom of the display indicates that multiple screens are available as output. Whenever a "--More--" prompt appears, the next available screen can be viewed by pressing the space bar. 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 ena. This might cause the router to prompt the user for a password if one has been set. If a "?" (question mark) is typed at the privileged EXEC mode prompt, the screen displays a longer list of commands than is available at the user EXEC mode prompt.

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

If a user wants to set the router clock but does not know the necessary command, the help function can be used to check for the correct command. The following exercise illustrates one of the many uses of the help function.

The task is to set the router clock. Assuming the command is not known, proceed using the following steps:

  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 automatically. 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.
 

Lab Activity

e-Lab Activity: Keyboard help in the CLI

This purpose of this lab is to learn the help system in the Cisco IOS.

   
 

Lab Activity

e-Lab Activity: IOS Auto-Completion

This purpose of this lab is to learn use the router auto-completion feature (TAB key) and the history buffer.

   
 

Web Links

help Command

http://www.cisco.com/en/US/products/sw/ iosswrel/ ps1835/ productscommand_ reference_ chapter09186a00800ca73c.html#1017835