mirror of
https://github.com/vyos/vyos-documentation.git
synced 2025-10-26 08:41:46 +01:00
129 lines
3.6 KiB
ReStructuredText
129 lines
3.6 KiB
ReStructuredText
.. _command-scripting:
|
|
|
|
Command Scripting
|
|
=================
|
|
|
|
VyOS supports executing configuration and operational commands non-interactively
|
|
from shell scripts.
|
|
|
|
To include VyOS specific functions and aliases you need to ``source
|
|
/opt/vyatta/etc/functions/script-template`` files at the top of your script.
|
|
|
|
.. code-block:: none
|
|
|
|
#!/bin/vbash
|
|
source /opt/vyatta/etc/functions/script-template
|
|
exit
|
|
|
|
Run configuration commands
|
|
--------------------------
|
|
|
|
Configuration commands are executed just like from a normal config session. For
|
|
example, if you want to disable a BGP peer on VRRP transition to backup:
|
|
|
|
.. code-block:: none
|
|
|
|
#!/bin/vbash
|
|
source /opt/vyatta/etc/functions/script-template
|
|
configure
|
|
set protocols bgp local-as 65536
|
|
set protocols bgp neighbor 192.168.2.1 shutdown
|
|
commit
|
|
exit
|
|
|
|
Run operational commands
|
|
------------------------
|
|
|
|
Unlike a normal configuration sessions, all operational commands must be
|
|
prepended with ``run``, even if you haven't created a session with configure.
|
|
|
|
.. code-block:: none
|
|
|
|
#!/bin/vbash
|
|
source /opt/vyatta/etc/functions/script-template
|
|
run show interfaces
|
|
exit
|
|
|
|
Other script language
|
|
---------------------
|
|
|
|
If you want to script the configs in a language other than bash you can have
|
|
your script output commands and then source them in a bash script.
|
|
|
|
Here is a simple example:
|
|
|
|
.. code-block:: python
|
|
|
|
#!/usr/bin/env python
|
|
print "delete firewall group address-group somehosts"
|
|
print "set firewall group address-group somehosts address '192.0.2.3'"
|
|
print "set firewall group address-group somehosts address '203.0.113.55'"
|
|
|
|
|
|
.. code-block:: none
|
|
|
|
#!/bin/vbash
|
|
source /opt/vyatta/etc/functions/script-template
|
|
configure
|
|
source < /config/scripts/setfirewallgroup.py
|
|
commit
|
|
|
|
|
|
Executing Configuration Scripts
|
|
-------------------------------
|
|
|
|
There is a pitfall when working with configuration scripts. It is tempting to
|
|
call configuration scripts with "sudo" (i.e., temporary root permissions),
|
|
because that's the common way on most Linux platforms to call system commands.
|
|
|
|
On VyOS this will cause the following problem: After modifying the configuration
|
|
via script like this once, it is not possible to manually modify the config
|
|
anymore:
|
|
|
|
.. code-block:: none
|
|
|
|
sudo ./myscript.sh # Modifies config
|
|
configure
|
|
set ... # Any configuration parameter
|
|
|
|
This will result in the following error message: ``Set failed`` If this happens,
|
|
a reboot is required to be able to edit the config manually again.
|
|
|
|
To avoid these problems, the proper way is to call a script with the
|
|
``vyattacfg`` group, e.g., by using the ``sg`` (switch group) command:
|
|
|
|
.. code-block:: none
|
|
|
|
sg vyattacfg -c ./myscript.sh
|
|
|
|
To make sure that a script is not accidentally called without the ``vyattacfg``
|
|
group, the script can be safeguarded like this:
|
|
|
|
.. code-block:: none
|
|
|
|
if [ "$(id -g -n)" != 'vyattacfg' ] ; then
|
|
exec sg vyattacfg -c "/bin/vbash $(readlink -f $0) $@"
|
|
fi
|
|
|
|
Postconfig on boot
|
|
------------------
|
|
|
|
The ``/config/scripts/vyos-postconfig-bootup.script`` script is called on boot
|
|
after the VyOS configuration is fully applied.
|
|
|
|
Any modifications done to work around unfixed bugs and implement enhancements
|
|
which are not complete in the VyOS system can be placed here.
|
|
|
|
The default file looks like this:
|
|
|
|
.. code-block:: none
|
|
|
|
#!/bin/sh
|
|
# This script is executed at boot time after VyOS configuration is fully
|
|
# applied. Any modifications required to work around unfixed bugs or use
|
|
# services not available through the VyOS CLI system can be placed here.
|
|
|
|
.. hint:: For configuration/upgrade management issues, modification of this
|
|
script should be the last option. Always try to find solutions based on CLI
|
|
commands first.
|