path: root/docs/configuration-overview.rst

.. _configuration-overview:

######################
Configuration Overview
######################

VyOS makes use of a unified configuration file for the entire system's
configuration: ``/config/config.boot``. This allows easy template
creation, backup, and replication of system configuration. A system can
thus also be easily cloned by simply copying the required configuration
files.

Terminology
===========

A VyOS system has three major types of configurations:

* **Active** or **running configuration** is the system configuration
  that is loaded  and currently active (used by VyOS). Any change in
  the configuration will have to be committed to belong to the
  active/running configuration.

* **Working configuration** is the one that is currently being modified
  in configuration mode. Changes made to the working configuration do
  not go into effect until the changes are committed with the
  :cfgcmd:`commit` command. At which time the working configuration will
  become the active or running configuration.

* **Saved configuration** is the one saved to a file using the
  :cfgcmd:`save` command. It allows you to keep safe a configuration for
  future uses. There can be multiple configuration files. The default or
  "boot" configuration is saved and loaded from the file
  ``/config/config.boot``.

Seeing and navigating the configuration
=======================================

.. opcmd:: show configuration

   View the current active configuration, also known as the running
   configuration, from the operational mode.

   .. code-block:: none

     vyos@vyos:~$ show configuration
     interfaces {
         ethernet eth0 {
             address dhcp
             hw-id 00:53:00:00:aa:01
         }
         loopback lo {
         }
     }
     service {
         ssh {
             port 22
         }
     }
     system {
         config-management {
             commit-revisions 20
         }
         console {
             device ttyS0 {
                 speed 9600
             }
         }
         login {
             user vyos {
                 authentication {
                     encrypted-password ****************
                 }
                 level admin
             }
         }
         ntp {
             server 0.pool.ntp.org {
             }
             server 1.pool.ntp.org {
             }
             server 2.pool.ntp.org {
             }
         }
         syslog {
             global {
                 facility all {
                     level notice
                 }
                 facility protocols {
                     level debug
                 }
             }
         }
     }

By default, the configuration is displayed in a hierarchy like the above
example, this is only one of the possible ways to display the
configuration. When the configuration is generated and the device is
configured, changes are added through a collection of :cfgcmd:`set` and
:cfgcmd:`delete` commands.

.. opcmd:: show configuration commands

   Get a collection of all the set commands required which led to the
   running configuration.

   .. code-block:: none

     vyos@vyos:~$ show configuration commands
     set interfaces ethernet eth0 address 'dhcp'
     set interfaces ethernet eth0 hw-id '00:53:dd:44:3b:0f'
     set interfaces loopback 'lo'
     set service ssh port '22'
     set system config-management commit-revisions '20'
     set system console device ttyS0 speed '9600'
     set system login user vyos authentication encrypted-password '$6$Vt68...QzF0'
     set system login user vyos level 'admin'
     set system ntp server '0.pool.ntp.org'
     set system ntp server '1.pool.ntp.org'
     set system ntp server '2.pool.ntp.org'
     set system syslog global facility all level 'notice'
     set system syslog global facility protocols level 'debug'

Both these ``show`` commands should be executed when in operational
mode, they do not work directly in configuration mode. There is a
special way on how to :ref:`run_opmode_from_config_mode`.

.. hint:: Use the ``show configuration commands | strip-private``
   command when you want to hide private data. You may want to do so if
   you want to share your configuration on the `forum`_.

.. _`forum`: https://forum.vyos.io


The config mode
---------------

When entering the configuration mode you are navigating inside a tree
structure, to enter configuration mode enter the command
:opcmd:`configure` when in operational mode.

.. code-block:: none

  vyos@vyos$ configure
  [edit]
  vyos@vyos#


.. note:: When going into configuration mode, prompt changes from
   ``$`` to ``#``.


All commands executed here are relative to the configuration level you
have entered. You can do everything from the top level, but commands
will be quite lengthy when manually typing them.

The current hierarchy level can be changed by the :cfgcmd:`edit`
command.

.. code-block:: none

  [edit]
  vyos@vyos# edit interfaces ethernet eth0

  [edit interfaces ethernet eth0]
  vyos@vyos#

You are now in a sublevel relative to ``interfaces ethernet eth0``, all
commands executed from this point on are relative to this sublevel. Use
eithe the :cfgcmd:`top` or :cfgcmd:`exit` command to go back to the top
of the hierarchy. You can also use the :cfgcmd:`up` command to move only
one level up at a time.

.. cfgcmd:: show

The :cfgcmd:`show` command within configuration mode will show the
working configuration indicating line changes with ``+`` for additions,
``>`` for replacements and ``-`` for deletions.

**Example:**

.. code-block:: none

 vyos@vyos:~$ configure
 [edit]
 vyos@vyos# show interfaces
  ethernet eth0 {
      description MY_OLD_DESCRIPTION
      disable
      hw-id 00:53:dd:44:3b:03
  }
  loopback lo {
  }
 [edit]
 vyos@vyos# set interfaces ethernet eth0 address dhcp
 [edit]
 vyos@vyos# set interfaces ethernet eth0 description MY_NEW_DESCRIPTION
 [edit]
 vyos@vyos# delete interfaces ethernet eth0 disable
 [edit]
 vyos@vyos# show interfaces
  ethernet eth0 {
 +    address dhcp
 >    description MY_NEW_DESCRIPTION
 -    disable
      hw-id 00:53:dd:44:3b:03
  }
  loopback lo {
  }

It is also possible to display all `set` commands within configuration
mode using :cfgcmd:`show | commands`

.. code-block:: none

  vyos@vyos# show interfaces ethernet eth0 | commands
  set address dhcp
  set hw-id 00:53:ad:44:3b:03

These commands are also relative to the level you are inside and only 
relevant configuration blocks will be displayed when entering a
sub-level.

.. code-block:: none

  [edit interfaces ethernet eth0]
  vyos@vyos# show
   address dhcp
   hw-id 00:53:ad:44:3b:03

Exiting from the configuration mode is done via the :cfgcmd:`exit`
command from the top level, executing :cfgcmd:`exit` from within a
sub-level takes you back to the top level.

.. code-block:: none

  [edit interfaces ethernet eth0]
  vyos@vyos# exit
  [edit]
  vyos@vyos# exit
  Warning: configuration changes have not been saved.

Comment
-------

.. cfgcmd:: comment <config node> "comment text"

   Add comment as an annotation to a configuration node.

   The ``comment`` command allows you to insert a comment above the
   ``<config node>`` configuration section. When shown, comments are
   enclosed with ``/*`` and ``*/`` as open/close delimiters. Comments
   need to be commited, just like other config changes.

   To remove an existing comment from your current configuration,
   specify an empty string enclosed in double quote marks (``""``) as
   the comment text.

   Example:

   .. code-block:: none

     vyos@vyos# comment firewall all-ping "Yes I know this VyOS is cool"
     vyos@vyos# commit
     vyos@vyos# show
      firewall {
          /* Yes I know this VyOS is cool */
          all-ping enable
          broadcast-ping disable
          ...
      }

   .. note:: An important thing to note is that since the comment is
      added on top of the section, it will not appear if the ``show
      <section>`` command is used. With the above example, the `show
      firewall` command would return starting after the ``firewall
      {`` line, hiding the comment.



Editing the configuration
=========================

The configuration can be edited by the use of :cfgcmd:`set` and
:cfgcmd:`delete` commands from within configuration mode. Configuration
commands are flattened from the tree into 'one-liner' commands shown in
:opcmd:`show configuration commands` from operation mode.

Commands are relative to the level where they are executed and all
redundant information from the current level is removed from the command
entered.

.. code-block:: none

  [edit]
  vyos@vyos# set interface ethernet eth0 address 192.0.2.100/24


.. code-block:: none

  [edit interfaces ethernet eth0]
  vyos@vyos# set address 203.0.113.6/24


These two commands above are essentially the same, just executed from
different levels in the hierarchy.

.. cfgcmd:: delete

   To delete a configuration entry use the :cfgcmd:`delete` command,
   this also deletes all sub-levels under the current level you've
   specified in the :cfgcmd:`delete` command. Deleting an entry will
   also result in the element reverting back to its default value if one
   exists.

   .. code-block:: none

     [edit interfaces ethernet eth0]
     vyos@vyos# delete address 192.0.2.100/24

.. cfgcmd:: commit

  Any change you do on the configuration, will not take effect until
  committed using the :cfgcmd:`commit` command in configuration mode.

  .. code-block:: none

    vyos@vyos# commit
    [edit]
    vyos@vyos# exit
    Warning: configuration changes have not been saved.
    vyos@vyos:~$

.. cfgcmd:: save

   In order to preserve configuration changes upon reboot, the
   configuration must also be saved once applied. This is done using the
   :cfgcmd:`save` command in configuration mode.

   .. code-block:: none

     vyos@vyos# save
     Saving configuration to '/config/config.boot'...
     Done

   .. code-block:: none

     vyos@vyos# save [tab]
     Possible completions:
       <Enter>       Save to system config file
       <file>        Save to file on local machine
       scp://<user>:<passwd>@<host>/<file> Save to file on remote machine
       ftp://<user>:<passwd>@<host>/<file> Save to file on remote machine
       tftp://<host>/<file>      Save to file on remote machine
     vyos@vyos# save tftp://192.168.0.100/vyos-test.config.boot
     Saving configuration to 'tftp://192.168.0.100/vyos-test.config.boot'...
     ######################################################################## 100.0%
     Done

.. cfgcmd:: exit [discard]

   Configuration mode can not be exited while uncommitted changes exist.
   To exit configuration mode without applying changes, the
   :cfgcmd:`exit discard` command must be used.

   All changes in the working config will thus be lost.

   .. code-block:: none

     vyos@vyos# exit
     Cannot exit: configuration modified.
     Use 'exit discard' to discard the changes and exit.
     [edit]
     vyos@vyos# exit discard


.. cfgcmd:: commit-confirm

   Commit the current set of changes if ``confirm`` is also entered
   within 10 minutes. Otherwise the system reboot into the previous
   configuration.


   What if you are doing something dangerous? Suppose you want to setup
   a firewall, and you are not sure there are no mistakes that will lock
   you out of your system. You can use confirmed commit. If you issue
   the ``commit-confirm`` command, your changes will be commited, and if
   you don't issue issue the ``confirm`` command in 10 minutes, your
   system will reboot into previous config revision.

   .. code-block:: none
   
      vyos@router# set interfaces ethernet eth0 firewall local name FromWorld
      vyos@router# commit-confirm 
      commit confirm will be automatically reboot in 10 minutes unless confirmed
      Proceed? [confirm]y
      [edit]
      vyos@router# confirm 
      [edit]


   .. note:: A reboot because you did not enter ``confirm`` will not
      take you necessarily to the *saved configuration*, but to the
      point before the unfortunate commit.


.. cfgcmd:: copy

   Copy a configuration element.

   You can copy and remove configuration subtrees. Suppose you set up a
   firewall ruleset ``FromWorld`` with one rule that allows traffic from
   specific subnet. Now you want to setup a similar rule, but for
   different subnet. Change your edit level to
   ``firewall name FromWorld`` and use ``copy rule 10 to rule 20``, then
   modify rule 20.


   .. code-block:: none
   
      vyos@router# show firewall name FromWorld 
       default-action drop
       rule 10 {
           action accept
           source {
               address 203.0.113.0/24
           }
       }
      [edit]
      vyos@router# edit firewall name FromWorld 
      [edit firewall name FromWorld]
      vyos@router# copy rule 10 to rule 20
      [edit firewall name FromWorld]
      vyos@router# set rule 20 source address 198.51.100.0/24
      [edit firewall name FromWorld]
      vyos@router# commit
      [edit firewall name FromWorld]


.. cfgcmd:: rename

   Rename a configuration element.

   You can also rename config subtrees:

   .. code-block:: none
   
      vyos@router# rename rule 10 to rule 5
      [edit firewall name FromWorld]
      vyos@router# commit
      [edit firewall name FromWorld]

   Note that ``show`` command respects your edit level and from this
   level you can view the modified firewall ruleset with just ``show``
   with no parameters.

   .. code-block:: none
   
      vyos@router# show 
       default-action drop
       rule 5 {
           action accept
           source {
               address 203.0.113.0/24
           }
       }
       rule 20 {
           action accept
           source {
               address 198.51.100.0/24
           }
       }
   

.. _run_opmode_from_config_mode:

Access opmode from config mode
==============================

When inside configuration mode you are not directly able to execute
operational commands.

.. cfgcmd:: run

  Access to these commands are possible through the use of the
  ``run [command]`` command. From this command you will have access to
  everything accessible from operational mode.

  Command completion and syntax help with ``?`` and ``[tab]`` will also
  work.

  .. code-block:: none

    [edit]
    vyos@vyos# run show interfaces
    Codes: S - State, L - Link, u - Up, D - Down, A - Admin Down
    Interface        IP Address                        S/L  Description
    ---------        ----------                        ---  -----------
    eth0             0.0.0.0/0                         u/u

Managing configurations
=======================

VyOS comes with an integrated versioning system for the system
configuration. It automatically maintains a backup of every previous
configuration which has been committed to the system. The configurations
are versioned locally for rollback but they can also be stored on a
remote host for archiving/backup reasons.

Local Archive
-------------

Revisions are stored on disk. You can view, compare and rollback them to
any previous revisions if something goes wrong.

.. opcmd:: show system commit

   View all existing revisions on the local system.

   .. code-block:: none

     vyos@vyos:~$ show system commit
     0   2015-03-30 08:53:03 by vyos via cli
     1   2015-03-30 08:52:20 by vyos via cli
     2   2015-03-26 21:26:01 by root via boot-config-loader
     3   2015-03-26 20:43:18 by root via boot-config-loader
     4   2015-03-25 11:06:14 by root via boot-config-loader
     5   2015-03-25 01:04:28 by root via boot-config-loader
     6   2015-03-25 00:16:47 by vyos via cli
     7   2015-03-24 23:43:45 by root via boot-config-loader


.. cfgcmd:: set system config-management commit-revisions <N>

   You can specify the number of revisions stored on disk. N can be in
   the range of 0 - 65535. When the number of revisions exceeds the
   configured value, the oldest revision is removed. The default setting
   for this value is to store 20 revisions locally.


Compare configurations
----------------------

VyOS lets you compare different configurations.

.. cfgcmd:: compare <saved | N> <M>

   Use this command to spot what the differences are between different
   configurations.

   .. code-block:: none

     vyos@vyos# compare [tab]
     Possible completions:
       <Enter>	Compare working & active configurations
       saved		Compare working & saved configurations
       <N>		Compare working with revision N
       <N> <M>	Compare revision N with M
       Revisions:
         0	   2013-12-17 20:01:37 root by boot-config-loader
         1	   2013-12-13 15:59:31 root by boot-config-loader
         2	   2013-12-12 21:56:22 vyos by cli
         3	   2013-12-12 21:55:11 vyos by cli
         4	   2013-12-12 21:27:54 vyos by cli
         5	   2013-12-12 21:23:29 vyos by cli
         6	   2013-12-12 21:13:59 root by boot-config-loader
         7	   2013-12-12 16:25:19 vyos by cli
         8	   2013-12-12 15:44:36 vyos by cli
         9	   2013-12-12 15:42:07 root by boot-config-loader
         10   2013-12-12 15:42:06 root by init

   The command :cfgcmd:`compare` allows you to compare different type of
   configurations. It also lets you compare different revisions through
   the :cfgcmd:`compare N M` command, where N and M are revision
   numbers. The output will describe how the configuration N is when
   compared to M indicating with a plus sign (``+``) the additional
   parts N has when compared to M, and indicating with a minus sign
   (``-``) the lacking parts N misses when compared to M.

   .. code-block:: none

     vyos@vyos# compare 0 6
     [edit interfaces]
     +dummy dum1 {
     +    address 10.189.0.1/31
     +}
     [edit interfaces ethernet eth0]
     +vif 99 {
     +    address 10.199.0.1/31
     +}
     -vif 900 {
     -    address 192.0.2.4/24
     -}


.. opcmd:: show system commit diff <number>

   Show commit revision difference.


The command above also lets you see the difference between two commits.
By default the difference with the running config is shown.

.. code-block:: none

   vyos@router# run show system commit diff 4
   [edit system]
   +ipv6 {
   +    disable-forwarding
   +}

This means four commits ago we did ``set system ipv6 disable-forwarding``.





Rollback Changes
----------------

You can rollback configuration changes using the rollback command. This
willn apply the selected revision and trigger a system reboot.

.. cfgcmd:: rollback <N>

   Rollback to revision N (currently requires reboot)

   .. code-block:: none

     vyos@vyos# compare 1
     [edit system]
     >host-name vyos-1
     [edit]

     vyos@vyos# rollback 1
     Proceed with reboot? [confirm][y]
     Broadcast message from root@vyos-1 (pts/0) (Tue Dec 17 21:07:45 2013):
     The system is going down for reboot NOW!

Remote Archive
--------------

VyOS can upload the configuration to a remote location after each call
to :cfgcmd:`commit`. You will have to set the commit-archive location.
TFTP, FTP, SCP and SFTP servers are supported. Every time a
:cfgcmd:`commit` is successfull the ``config.boot`` file will be copied
to the defined destination(s). The filename used on the remote host will
be ``config.boot-hostname.YYYYMMDD_HHMMSS``. 

.. cfgcmd:: set system config-management commit-archive location <URI>

   Specify remote location of commit archive as any of the below
   :abbr:`URI (Uniform Resource Identifier)`

   * ``scp://<user>:<passwd>@<host>/<dir>``
   * ``sftp://<user>:<passwd>@<host>/<dir>``
   * ``ftp://<user>:<passwd>@<host>/<dir>``
   * ``tftp://<host>/<dir>``

.. note:: The number of revisions don't affect the commit-archive.

.. note:: You may find VyOS not allowing the secure connection because
   it cannot verify the legitimacy of the remote server. You can use
   the workaround below to quickly add the remote host's SSH
   fingerprint to your ``~/.ssh/known_hosts`` file:

   .. code-block:: none

     vyos@vyos# ssh-keyscan <host> >> ~/.ssh/known_hosts

Restore Default
---------------

In the case you want to completely delete your configuration and restore
the default one, you can enter the following command in configuration
mode:

.. code-block:: none

  load /opt/vyatta/etc/config.boot.default

You will be asked if you want to continue. If you accept, you will have
to use :cfgcmd:`commit` if you want to make the changes active.

Then you may want to :cfgcmd:`save` in order to delete the saved
configuration too.

.. note:: If you are remotely connected, you will lose your connection.
   You may want to copy first the config, edit it to ensure
   connectivity, and load the edited config.