Question Mail subdomains with wrong TLS certificate (e.g. imap.example.tld)

[sneppa]

Server operating system version

Ubuntu 22.04.4 LTS

Plesk version and microupdate number

Plesk Obsidian 18.0.58 Update #2

Hi,

currently I'm migrating the websites of a plesk server into a new plesk server.
In the old configuration the users are using the server domain to send/receive emails.
On the new plesk server I have activated the imap.user.tld, smtp.user.tld feature.

Today I migrated 3 websites and have the same issue on every domain:
Instead of the imap.user.tld the client gets the server certificate, configured in "Tools & Einstellungen > SSL/TLS-Zertifikate":


In the mail settings of the websites, the certificate of the user.tld is set:


I checked the certificate with:

echo QUIT | openssl s_client -connect smtp.user.tld:465

It returns the server certificate, not the certificate of the users tld.

I reissued all let's encrypt certificates, rebooted the server, but still the same issue.

Similar issue was described in: Resolved - Certificate Invalid

Do you have any recommendations or should I contact the plesk support?

Thank you!

 

[Kaspar]

As far as I know, in Plesk the only the domain itself is secured with SNI. Meaning that by default only the domain itself is useable for secured email connections. (And the server hostname of course.) Alternatively you could add imap and smtp as a subdomain to each domain. But that might not be a very workable solution.

There is a feature request on UserVoice for a somewhat similar feature you can vote for.