Pre and Post Domain Modification Scripts

Introduction to Modification Scripts

Virtualmin provides a method for you to have your own scripts (typically shell scripts, but Perl and Python also work) run before or after a virtual server is created, modified or deleted.

This can be useful if you want to have some setup performed for each new domain that is beyond Virtualmin's built-in capabilities. They can also be used to validate changes made by a user before they happen, such as creation of a domain with settings that are inappropriate for your system.

Virtualmin lets you specify a script to be run before any action is performed, and a separate script to be run after. If the pre-change script fails (by returning a non-zero exit status), whatever action was going to happen will be blocked.

Example Scripts

Let's imagine you wanted each new virtual server to have a file it is home directory downloaded from some website. A post-creation script to implement this would look like :

  wget -O somefile.tar.gz ""

If you had some external database that you wanted each new domain user to have an account in, you could automate this with a script like :

if [ "$VIRTUALSERVER_PARENT" = "" ]; then

Setting Pre and Post Modification Scripts

Once you have written a script, you can tell Virtualmin which scripts to run before or after some action is performed as follows :

  1. Login as root and go to System Settings -> Virtualmin Configuration.
  2. Select the Actions upon server and user creation category.
  3. In the Command to run before making changes to a server field enter the full path to your pre-modification command, if any.
  4. In the Command to run after making changes to a server field, enter the full path to the post-modification command.
  5. Click Save.

Make sure the script(s) are executable, or else Virtualmin will not be able to run them.

Variables Available In Scripts

Every attribute of a virtual server is available via environment variables, all of which start with the $VIRTUALSERVER_ prefix. These are the same variables that can be used in email and other templates, as documented on the Template Variable Listing page. However, all script variables have $VIRTUALSERVER_ at the start, like $VIRTUALSERVER_DOM or $VIRTUALSERVER_PASS.

The action being performed can be determined by looking at the $VIRTUALSERVER_ACTION environment variable, which will be set to one of :

CREATE_DOMAIN A new virtual server is being created MODIFY_DOMAIN Some attribute of a virtual server is being changed DELETE_DOMAIN A virtual server has been deleted DISABLE_DOMAIN The virtual server is being temporarily disabled ENABLE_DOMAIN The virtual server is being re-enabled DBNAME_DOMAIN The database login for a virtual server is being changed DBPASS_DOMAIN The database password for a virtual server is being changed RESTORE_DOMAIN A virtual server is being restored from a backup