.. _cli: ### CLI ### The VyOS :abbr:`CLI (Command-Line Interface)` comprises an :ref:`commandtree_operationmode` and a :ref:`commandtree_configmode`. Operational mode allows for commands to perform operational system tasks and view system and service status, while configuration mode allows for the modification of system configuration. The :ref:`command tree page` lists available commands and their functions. The CLI provides a built-in help system. In the CLI the ``?`` key may be used to display available commands. The ``TAB`` key can be used to auto-complete commands and will present the help system upon a conflict or unknown value. For example typing ``sh`` followed by the ``TAB`` key will complete to ``show``. Pressing ``TAB`` a second time will display the possible sub-commands of the ``show`` command. .. code-block:: none vyos@vyos:~$ s[tab] set show Example showing possible show commands: .. code-block:: none vyos@vyos:~$ show [tab] Possible completions: arp Show Address Resolution Protocol (ARP) information bridge Show bridging information cluster Show clustering information configuration Show running configuration conntrack Show conntrack entries in the conntrack table conntrack-sync Show connection syncing information date Show system date and time dhcp Show Dynamic Host Configuration Protocol (DHCP) information dhcpv6 Show status related to DHCPv6 disk Show status of disk device dns Show Domain Name Server (DNS) information file Show files for a particular image firewall Show firewall information flow-accounting Show flow accounting statistics hardware Show system hardware details history show command history host Show host information incoming Show ethernet input-policy information : q You can scroll up with the keys ``[Shift]+[PageUp]`` and scroll down with ``[Shift]+[PageDown]``. When the output of a command results in more lines than can be displayed on the terminal screen the output is paginated as indicated by a ``:`` prompt. When viewing in page mode the following commands are available: * ``q`` key can be used to cancel output * ``space`` will scroll down one page * ``b`` will scroll back one page * ``return`` will scroll down one line * ``up-arrow`` and ``down-arrow`` will scroll up or down one line at a time respectively * ``left-arrow`` and ``right-arrow`` can be used to scroll left or right in the event that the output has lines which exceed the terminal size. To enter configuration mode use the ``configure`` command: .. code-block:: none vyos@vyos:~$ configure [edit] vyos@vyos:~# .. note:: Prompt changes from ``$`` to ``#``. To exit configuration mode, type ``exit``. .. code-block:: none vyos@vyos:~# exit exit vyos@vyos:~$ See the configuration section of this document for more information on configuration mode.