Hello! I followed this tutorial to create a Let's Encrypt SSL certificate for the main domain of the hostnames of the main domain of my server: mail.azuritetechs.com smtp.azuritetechs.com imap.azuritetechs.com I am wondering how to do the same process for the rest of the domains, for example the sample domain sampledomain.com with these hostnames: mail.sampledomain.com smtp.sampledomain.com imap.sampledomain.com I am using Ubuntu 18.04, ISPConfig 3.2.6. and Apache. Please let me know how and what additional information I can share with you. I really appreciate your help. Thank you!
Choose one of the domains as parent domain, create the rest as alias domains for that parent website. Then they are added to the Let's Encrypt certificate for the parent website, unless you tick the "Don't add to Let's Encrypt certificate" box. It may not be a good idea to use those smtp and imap hostnames as e-mail MX and mail server names, though. I use only the main name of the server in e-mail hostnames.
Normally you would not do that. You choose one domain, typically your company domain as a hoster, and create the subdomains for only one domain. Theoretically, you could do this for other domains as well, but it will likely bring you in trouble with SSL cert renewals in future as the cert will fail for all domains if one of them is unreachable. Plus, the cert is limited to max 100 subdomains by LE, so you can not scale your system. That's why all larger hosters or hosters that like to have the opportunity in future to grow their hosting business always chose a single domain.
What do you mean? Do I use mail.azuritetechs.com, smtp.azuritetechs.com, imap.azuritetechs.com for all other domains? Thank you!
