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

live 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 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 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

show configuration

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

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 set and delete commands.

show configuration commands

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

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 Access 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.

The config mode

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

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 edit command.

[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 top or exit command to go back to the top of the hierarchy. You can also use the up command to move only one level up at a time.

show

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

Example:

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 show | commands

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.

[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 exit command from the top level, executing exit from within a sub-level takes you back to the top level.

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

Editing the configuration

The configuration can be edited by the use of set and delete commands from within configuration mode.

set
Use this command to set the value of a parameter or to create a new element.

Configuration commands are flattened from the tree into ‘one-liner’ commands shown in 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.

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

delete

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

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

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

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

Use this command to preserve configuration changes upon reboot. By default it is stored at /config/config.boot. In the case you want to store the configuration file somewhere else, you can add a local path, an SCP address, an FTP address or a TFTP address.

vyos@vyos# save
Saving configuration to '/config/config.boot'...
Done
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
exit [discard]

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

All changes in the working config will thus be lost.

vyos@vyos# exit
Cannot exit: configuration modified.
Use 'exit discard' to discard the changes and exit.
[edit]
vyos@vyos# exit discard
commit-confirm <minutes>

Use this command to temporarily commit your changes and set the number of minutes available for validation. confirm must be entered within those minutes, otherwise the system will reboot into the previous configuration. The default value is 10 minutes.

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.

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.

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.

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]
rename

Rename a configuration element.

You can also rename config subtrees:

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.

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
     }
 }
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:

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.

Access opmode from config mode

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

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.

[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.

show system commit

View all existing revisions on the local system.

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
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 100 revisions locally.

Compare configurations

VyOS lets you compare different configurations.

compare <saved | N> <M>

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

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 compare allows you to compare different type of configurations. It also lets you compare different revisions through the 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.

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
-}
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.

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 will apply the selected revision and trigger a system reboot.

rollback <N>

Rollback to revision N (currently requires reboot)

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 commit. You will have to set the commit-archive location. TFTP, FTP, SCP and SFTP servers are supported. Every time a 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.

set system config-management commit-archive location <URI>

Specify remote location of commit archive as any of the below URI

  • 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:

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

Saving and loading manually

You can use the save and load commands if you want to manually manage specific configuration files.

When using the save command, you can add a specific location where to store your configuration file. And, when needed it, you will be able to load it with the load command:

load <URI>
Use this command to load a configuration which will replace the running configuration. Define the location of the configuration file to be loaded. You can use a path to a local file, an SCP address, an SFTP address, an FTP address, an HTTP address, an HTTPS address or a TFTP address.
vyos@vyos# load
Possible completions:
  <Enter>                                  Load from system config file
  <file>                                   Load from file on local machine
  scp://<user>:<passwd>@<host>/<file>      Load from file on remote machine
  sftp://<user>:<passwd>@<host>/<file>     Load from file on remote machine
  ftp://<user>:<passwd>@<host>/<file>      Load from file on remote machine
  http://<host>/<file>                     Load from file on remote machine
  https://<host>/<file>                    Load from file on remote machine
  tftp://<host>/<file>                     Load from file on remote machine

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:

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

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

Then you may want to 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.