Using the Command-Line Interface : Overview of the CLI
  
Overview of the CLI
The CLI has the following modes:
•  User - When you start a CLI session, you begin in the default, user mode. From user mode you can run common network tests such as ping and view network configuration settings and statistics. You do not enter a command to enter user mode. To exit this mode, enter exit at the command line.
•  Enable - To access system monitoring commands, you must enter enable mode. From enable mode, you can enter any enable mode command or enter configuration mode. You must be an administrator user to enter enable mode. In enable mode you can perform basic system administration tasks, such as restarting and rebooting the system. To exit this mode, enter disable at the command line.
You cannot enter enable mode if you are a monitor user.
•  Configuration - To make changes to the running configuration, you must enter configuration mode. To save configuration changes to memory, you must enter the write memory command. To enter configuration mode, you must first be in enable mode. To exit this mode, enter exit at the command line.
The commands available to you depend on which mode you are in. Entering a question mark (?) at the system prompt provides a list of commands for each command mode.
Mode
Access Method
System Prompt
Exit Method
Description
user
Each CLI session begins in user mode.
host >
exit
•  Perform common network tests, such as ping.
•  Display system settings and statistics.
enable
Enter the enable command at the system prompt while in user-mode.
host #
disable
•  Perform basic system administration tasks, such as restarting and rebooting the system.
•  Display system data and statistics.
•  Perform all user-mode commands.
configuration
Enter the configure terminal command at the system prompt while in enable-mode.
host (config) #
exit
•  Configure system parameters.
•  Perform all user and enable-mode commands.