Specifications

A-6
Cisco 1800 Series Integrated Services Routers (Fixed) Software Configuration Guide
OL-6426-02
Appendix A Cisco IOS Software Basic Skills
Using Commands
Using Commands
This section provides some tips about entering Cisco IOS commands at the command-line interface
(CLI).
Abbreviating Commands
You only have to enter enough characters for the router to recognize the command as unique. This
example shows how to enter the show version command:
Router # sh v
Undoing Commands
If you want to disable a feature or undo a command you entered, you can enter the keyword no before
most commands; for example, no ip routing.
Command-Line Error Messages
Table A-3 lists some error messages that you might encounter while using the CLI to configure your
router.
Ta b l e A-3 Common CLI Error Messages
Error Message Meaning How to Get Help
% Ambiguous command:
"show con"
You did not enter enough
characters for your router to
recognize the command.
Reenter the command, followed
by a question mark (?) with no
space between the command and
the question mark.
The possible keywords that you
can enter with the command are
displayed.
% Incomplete command.
You did not enter all of the
keywords or values required by
this command.
Reenter the command, followed
by a question mark (?) with no
space between the command and
the question mark.
The possible keywords that you
can enter with the command are
displayed.
% Invalid input detected at
‘^’ marker.
You entered the command
incorrectly. The error occurred
where the caret mark (^) appears.
Enter a question mark (?) to
display all of the commands that
are available in this
command
mode.