Our current setup is pretty simple, we have a regex capture to ensure that the incoming request is a valid ascii domain name and we serve all our traffic from that. Great ... for us.
However, our customers, with about 12000 domain names at present have started to become quite vocal about having HTTPS on their websites, to which we provide a custom CMS and website package, which means we're about to create a new Nginx layer in front of our current servers to terminate TLS. This will require us to set up vhosts for each certificate issued with server names which match what's in the certificate's SAN.
To keep this simple we're currently thinking about just having each domain, and www subdomain, on its own certificate (LetsEncrypt) and vhost but that is going to lead, approximately, to the number of vhosts mentioned in the subject line. As such I wanted to put the feelers out to see if anyone else had tried to work with large numbers of vhosts and any issues which they may have come across.
Kind regards,
Richard