Cisco Command Christmas Calendar #1: enable / configure terminal

Hello! It's December and 24 days to Christmas. I thought it would be fun to do a "Cisco Command Christmas Calendar" series for the next 24 days where we look at basic Cisco commands or command combinations, one for each day of December leading up to Christmas. Most of the commands you're probably familiar with but a quick refresh is always useful. Let's kick off with the most obvious commands: enable and configure terminal. These are so obvious that I didn't want to put them in separate posts.

The enable and configure terminal, or en and conf t for short, are wired in a network engineer's nervous system. The commands are so encoded in muscle memory that you don't even have to think to type them, it's an automatic process whenever you want to configure anything on a Cisco device.

Commonly, the enable command is used to change the privilege level from user EXEC mode (privilege level 0; lowest) to privileged EXEC mode (privilege level 15; highest). User EXEC mode has minimal access to view or edit device configuration, privileged EXEC mode has full access. Because of this, privileged EXEC mode should be and often is protected by a password. Note that the prompt for user EXEC mode is the greater than symbol (>), and the prompt for privileged EXEC mode is the number sign (#).

Router> enable

To exit back to the user EXEC mode, use the disable command.

Router# disable

In addition to changing between the user EXEC and privileged EXEC mode, the enable command can be used to access a CLI view. CLI views are defined by the administrator and restrict user access to specified CLI and configuration information. The enable view view-name command is used to switch from one view to another.

Router# enable view neteng
00:28:23:%PARSER-6-VIEW_SWITCH:successfully set to view 'neteng'.
Router# ?
Exec commands:
  configure  Enter configuration mode
  enable     Turn on privileged commands
  exit       Exit from the EXEC
  show       Show running system information
Router# show ?
  ip       IP information
  parser   Display parser information
  version  System hardware and software status

You can use the ? to see which commands are available in the specified view.

The configure terminal command is used to enter the global configuration mode. In this mode, the commands are written into the running configuration as soon as you enter them (IOS devices). Note that the system prompt changes from the # sign to (config)# to indicate the device is in global configuration mode.

Router# configure terminal

To leave global configuration mode and return to privileged EXEC mode, type exit or press Ctrl-Z.

Router(config)# exit