How to Delete Virtual Server in Virtualmin
How to Delete/Remove a Virtual Server created in Virtualmin
Login to your webmin control panel using the root password. Open any webbrowser and type the below URL in browser to access webmin control panel.
Link to access webmin : https://yourServerHostname:10000
OR
https://yourServerIPaddress:10000

Link to access Webmin
You can access webmin using any of the above url. Your “yourServerHostname” should be replaced with the actual hostname of the server. “yourServerIPaddress” should be replaced with actual Server IP address.
Enter the webmin root password to access webmin control panel.
Username : root
Password : Enter the root password of the server
Select “Virtualmin” and select the “domain” in the dropdown you wish to delete.
Click on “Disable and Delete”. Under “Disable and Delete” you can see “Delete Virtual Server”

Remove Domain from Webmin Server
Note : This will delete the virtual server and you will lose all the data in this domain. Take a backup before deleting the domain.
You will see a warning before deleting the virtual server

Delete Domain Virtual Server in Webmin
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Are you sure you want to delete the virtual server domain.com, which has 24 Mb of files? The following features will be deleted :
Administration user – The administration user and group for this virtual server will be deleted.
Home directory – The home directory for this virtual server, containing all website and otherwise, will be deleted.
BIND DNS domain – All DNS records in the domain and any BIND options will be deleted.
Mail for domain – The mail server will no longer accept email for this domain.
Apache website – All Apache directives in the virtual host will be removed.
Log file rotation – The Logrotate configuration for the virtual server’s log files will be deleted.
MySQL database – All MySQL databases, all tables and the server’s MySQL login will be deleted.
Webmin login – The Webmin user for this virtual server will be deleted.
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Click on “Yes, Delete it” to confirm.