CLI Overview

The JUNOS CLI uses industry-standard tools and utilities to provide a set of commands for monitoring and configuring a routing platform. You type commands on a line and press Enter to execute them. The CLI provides command help, command completion, and Emacs-style keyboard sequences for moving around on the command line and scrolling through a buffer of recently executed commands.

The commands in the CLI are organized hierarchically, with commands that perform a similar function grouped together under the same level. For example, all commands that display information about the device system and system software are grouped under the show command, and all commands that display information about the routing table are grouped under the show route command. The hierarchical organization results in commands that have a regular syntax and provides the following features that simplify CLI use:

• Consistent command names—Commands that provide the same type of function have the same name, regardless of the portion of the software they are operating on. For example, all show commands display software information and statistics, and all clear commands erase various types of system information.
• Lists and short descriptions of available commands—Information about available commands is provided at each level of the CLI command hierarchy. If you type a question mark (?) at any level, you see a list of the available commands along with a short description of each command.
• Command completion—Command completion for command names (keywords) and command options is also available at each level of the hierarchy. In the CLI terminal you can do one of the following for command completions:
  • Type a partial command name followed immediately by a question mark (with no intervening space), to see a list of commands that match the partial name you typed.
  • Press the Spacebar to complete a command or option that you have partially typed. If the partially typed letters begin a string that uniquely identifies a command, the complete command name appears. Otherwise, a prompt indicates that you have entered an ambiguous command, and the possible completions are displayed.

    The Tab key option is currently not available on the CLI terminal.

The CLI has two modes:

• Operational mode—Complete set of commands to control the CLI environment, monitor and troubleshoot network connectivity, manage the device, and enter configuration mode.
• Configuration mode—Complete set of commands to configure the device.

For more information about the JUNOS CLI, see the Junos OS CLI User Guide.