Wrong SSL certificate in use for "subdomain"

[lowprofile]

Hi,


Having a strange issue. Some clients (newly added) we include the "mail.clientdomain.com" domain in letsencrypt SSL. Somehow it doesnt use the correct SSL cert for that particular subdomain. DNS settings are correct set up with an A record pointing to server IP.

If i browse the "mail.clientdomain.com" i can see it use the "serverhostname.com" cert instead of "mail.clientdomain" which we have generated.
Now the odd part is, if you browse the main domain for client, "clientdomain.com" and look inside the cert, you can see the mail, www and root domain available in the cert. But somehow the "subdomain" (mail.clientdomain) is using the incorrect server certificate.

This issue is new. Some advices? There is nothing custom httpd added or anything. How to troubleshoot best?

Note: The domain "mail.clientdomain.com" is not added as an ALIAS or domain. Just included in the CERT generation letsencrypt. Thats how i done it for several hundreds clients and for years. Working fine.

rebuild conf and build update etc - everything has been tried.

 

[lowprofile]

Alright, it seems like a build dovecot and build exim/exim_conf did fix it.
But you cannot troubleshoot SSL cert by looking up mail.clientdomain.com - that would always show server cert. FYI