I have a Let's Encrypt SSL installed in the primary domain of a Wordpress Multisite. Need one for alias subsites too

[dpeschio]

My domain is: AshevilleAleTrail.com

I can login to a root shell on my machine (yes or no, or I don’t know): Yes

I’m using a control panel to manage my site (no, or provide the name and version of the control panel): Plesk

I am running a Wordpress Multisite. The primary domain is aletrailsofamerica.com where I have a LE SSL instaled and working. Inside the aletrailsofamerica.com Wordpress multisite we have additional websites like AshevilleAleTrail.com which are their own unique sites, but are alises of aletrailsofamerica.com. So if you go to AshevilleAleTrail.com it is a different site than CharlotteAleTrail.com, but the file path for all files will be aletrailsofamerica.com/*. We are using a domain mapping plugin to get all this to work. I need to be able to use https for aliases. How can I use the SSL installed for aletrailsofamerica.com to cover the alises or how do generate individual ssls for them?

[serverco]

I’m not sure if you can do it with the plesk plugin, but you should be able to do it with certbot or one of the alternate clients.

Since wordpress is determining what the server sees, then the single cert will need to cover all the domain names, as long as you have less than 100 though that should be fine.

For generating the cert there are a couple of options. You can use webroot and provide a different webroot for each domain or (I think the easier ), just set a redirect for all .well-known/acme-challenge requests to the same place ( in your apache / nginx / other config ) and then you can use a single webroot location.

Once you have the cert, I’d personally just set up a symlink in the storage place that plesk uses for your cert, to where letsencrypt stores the cert ( this may already be done if you used the letsencrypt plugin for plesk).