I am moving some users from one server ('new.server.com') to another ('old.server.com'). Currently, these users use 'old.server.com' in their POP3, IMAP and SMTP client configurations. I would like new.server.com to accept secure IMAP and SMTP connections for old.server.com so that the users don't have to change their mail client settings.
If I set mail_sni=1 in directadmin.conf, add 'old.server.com' as a subdomain in my admin user account, and add a Let's Encrypt certificate for old.server.com via User Level -> SSL Certficates, will that work so that the users don't to have to change their settings? I'm hoping to avoid phone calls about certificate errors. I also want to be sure that exim/dovecot don't limit the users that can use old.server.com since it will be under my admin user.
Or is there a better way to go about this? I do have an extra IP address that I could use.
If I set mail_sni=1 in directadmin.conf, add 'old.server.com' as a subdomain in my admin user account, and add a Let's Encrypt certificate for old.server.com via User Level -> SSL Certficates, will that work so that the users don't to have to change their settings? I'm hoping to avoid phone calls about certificate errors. I also want to be sure that exim/dovecot don't limit the users that can use old.server.com since it will be under my admin user.
Or is there a better way to go about this? I do have an extra IP address that I could use.