Issue Use webmail.domain as a valid dovecot secured hostname

[nuno.pereira]

Server operating system version

CentOS Linux release 7.9.2009 (Core)

Plesk version and microupdate number

Plesk Obsidian Version 18.0.46

For mail only domains, the certificate issued by Let's Encrypt is valid only for webmail.domain, and webmail is secure.

However, for POP3/IMAP/SMTP access by dovecot, even if Plesk domain configuration is indicating that we should use domain for incoming and outgoing mail server, that's not the case, as it's outside. So we use mail.domain as the mail server.

When using the Let's Encrypt certificate to secure the mail, as well as for webmail, this is the configuration added by Plesk to dovecot:

# grep -r <domain> /etc/dovecot/conf.d/
/etc/dovecot/conf.d/14-plesk-sni-<domain>.conf:local_name <domain> {
/etc/dovecot/conf.d/14-plesk-sni-mail.<domain>.conf:local_name mail.<domain> {

# cat /etc/dovecot/conf.d/14-plesk-sni-<domain>.conf /etc/dovecot/conf.d/14-plesk-sni-mail.<domain>.conf
#ATTENTION!
#
#DO NOT MODIFY THIS FILE BECAUSE IT WAS GENERATED AUTOMATICALLY,
#SO ALL YOUR CHANGES WILL BE LOST THE NEXT TIME THE FILE IS GENERATED.

local_name <domain> {
  ssl_cert = </usr/local/psa/var/certificates/scfXPy1p1
  ssl_key = </usr/local/psa/var/certificates/scfXPy1p1
}
# cat /etc/dovecot/conf.d/14-plesk-sni-mail.<domain>.conf
#ATTENTION!
#
#DO NOT MODIFY THIS FILE BECAUSE IT WAS GENERATED AUTOMATICALLY,
#SO ALL YOUR CHANGES WILL BE LOST THE NEXT TIME THE FILE IS GENERATED.

local_name mail.<domain> {
  ssl_cert = </usr/local/psa/var/certificates/scfXPy1p1
  ssl_key = </usr/local/psa/var/certificates/scfXPy1p1
}

However, apart from <domain> is not working, as it's located elsewhere, by using mail.<domain> as incoming and outgoing mail server, we get an error from the client (namely Outlook) that the certificate is invalid (was issued for webmail.<domain>), and we use webmail.<domain> as mail server, as it's not configured by dovecot.

Is there a possibility to change dovecot's configuration, so that it also uses webmail.<domain> as a valid mail server, in particular when the domain is mail only?

 

[IA-Plesk]

We also have clients that only have email service. Not allowing the use of customerdomain.tld as mail server on email client .
How can we configure webmail.customerdomain.tld as a server name indication (SNI)?
A good workaround was Plesk add webmail.customerdomain.tld as a server name indication (SNI).