Secure sub-domains only

Help
1

Hi! I have a main domain, let’s call it example.com on one server, then I have admin.example.com on a different server and dev.example.com on another server.
What is the best way to generate SSL certificates only for each subdomain, leaving the main domain unmodified.

My domain is: example.dom

My web server is : Nginx

The operating system my web server runs on is : Ubuntu 18.04

My hosting provider, if applicable, is: AWS

I can login to a root shell on my machine: yes

2

Hi @manus

there is no "best way".

Create these two certificates, job is done. There is no relation required between your main domain and your subdomains.

3

If the systems can individually run ACME clients, then you can treat them as separate systems.
Each doing only the local FQDN.