DNS config for Virtualmin feature “Send outgoing email for domain from IP”


I would need some help from you :slight_smile:

We host a mail server and three domains on a dedicated machine with Virtualmin, each of them with their own IP address. Due to hardware issues we had to move to a new server and also got new IPs. The default IP address which was/is used for the mail server was and still is on Microsofts blacklist. As it turned out to be much more complicated to get the IP off the blacklist we decided to use Virtualmins feature “Send outgoing email for domain from IP” to be at least able to send mails to our customers. Sending E-Mails through our shop system works fine but with Thunderbird we receive SSL-cert-errors. The reason for this error is that not the SSL-cert from the mail server gets delivered to Thunderbird but instead the SSL-cert from the shop gets delivered. The reason for this is (I think) a DNS-misconfiguration from us.

x.x.x.1 mail server
x.x.x.2 site 1
x.x.x.3 site 2
x.x.x.4 site 3

A-records for the mail server:
(Hostname of the Mailserver is “mail.mailserver.com”)

Host: IP:

  •          x.x.x.1

Mail x.x.x.1

  •          x.x.x.2

Mail x.x.x.2

  •          x.x.x.3

Mail x.x.x.3

  •          x.x.x.4

Mail x.x.x.4

We wanted the mail server to be reachable under all IPs (reverse dns entries) but for Thunderbird the IP for the mail server might be x.x.x.3 and Virtualmin delivers the SSL-cert for the site 2 and not for the mail server.

I am sure there is a proper configuration to avoid this. It would be great if somebody could help out.