Setting up WordPress multisite with Letsencrypt SSL certificates in Webmin/Virtualmin is actually fairly east. This guide assumes you have your multisite working. You need a domain to hang all the multi-sites of (parent domain). The TLD .xyz is fairly cheap so I use them.
Before doing this get your parent domain and setup multisite.
There a 3 steps to this (instructions below)
- Enable SSL on Parent Domain
- Setup Domain Alias
- Setup SSL Certificate
Enable SSL on Parent Domain
- Select the parent domain in Virtualmin
- expand Enables Features,
- ensure Apache SSL website enabled? is chercked.
- Click Save Virtual Server.
Setup Domain Alias
- Login to virtualmin and select domain to create alias under
- Select ‘Create Virtual Server’ top left
- Select ‘alias of’ tab at top (either create option with or without email aliuses’
- Fill in Domain Name and
- click Create Server
Setup Letsencrypt SSL Certificate
Here we will setup a Lets Encript certificate whitch are free and work great.
- Go to Server Configuration -> Manage SSL Certificate.
- Add the domains to Domain names listed here (best to add the parent domain and the multisite domain)
- Click on Request Vertificates.