It allows you to administer your server through an simple interface.
With Webmin, you can change settings for common packages on the fly.
In this tutorial, you'll install and configure Webmin on your server and secure access to the interface with a valid certificate using Let's Encrypt.
Before you can apply a valid certificate, you have to set the server's hostname.This is because the server has generated a self-signed certificate.Allow the exception to continue so you can replace the self-signed certificate with one from Let's Encrypt. Sign in with the username root and your current password for the root user.Look for the System hostname field and lick on the link to the right, as shown in the following figure: This will take you to the Hostname and DNS Client page.Locate the Hostname field, and enter your Fully-Qualified Domain Name into the field.