Hi all, I want to move a domain under Cloudflare which has many subdomains (hostnames) that point to several servers that hold email and web. I will set up CloudFlare accordingly, but my question goes what I should do to be sure that the cert of the email servers particularly (dovecot/postfix) will work. Be valid as per Cloudflare to avoid having TLS errors/warning to the clients side. I hope it is clear what I want to outline. Thanks
LE certs will work for all A and AAAA records in CloudFlare, where you do not turn on the CloudFlare proxy. And for mail, you can't turn on the proxy anyway, as far as I know. For website (sub) domains where you have CloudFlare turned on, simply use a self-signed SSL cert in the website in ISPConfig, and in CloudFlare, turn on Full SSL mode (but not fully strict).
