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Issue The reverse DNS does not match SMTP Banner

Alakide

New Pleskian
Hello,

I'm looking for help because I've dealing with this to much time. Here is the problem.

I have a VPS with Plesk Obsidian 18.0.35 and 3 diferent IPs

IP-A (server main dedicated IP)
IP-B (dedicated IP for a customer)
IP-C (shared IP for everyone else, arround other 15 domains)

The host name of our VPS is "server2.ourdomain.com"
I'm useing the main server IP on our webpage and email. If we test our email on MX Tool Box we got a pefrect score in the results.

The problem comes if one of our customers send a email, the MX Tool Box sent us a Warning that said that the reverse DNS does not contain the hostname, implying that the domain from which the mail was sent is different from the server name (server2.ourdomain.com). The consequence of this has been that they are beginning to reject emails from our customers.

I was wondering if anyone have any idea of how to solve this. I've tried several solutions but they have only led me to have more serious problems in our DNS.

Best Regards!!!
 
According my knowledge you can change it only by SSH # etc/postfix then in main.cf you can force some smtp behaviors. Backup this file first!!! By editing you can crash postfix very easy.
 
rDNS is set for an IP address in the router of your data center. If your server uses different IP addresses, you can set different rDNS entries for each IP in the network configuration of your data center, so that each IP will resolve to the appropriate domain name. This is nothing to do on your server, but it needs to be done in your data center for the IPs that you are using.
 
for this option
Outgoing mail mode: what you recommend?

1- Send from the specified IP addresses
2- Send from domain IP addresses

support guys told me the option #2
 
rDNS is set for an IP address in the router of your data center. If your server uses different IP addresses, you can set different rDNS entries for each IP in the network configuration of your data center, so that each IP will resolve to the appropriate domain name. This is nothing to do on your server, but it needs to be done in your data center for the IPs that you are using.

Do you see an easy DNS-based fix to have multiple domains (each dedicated IP) to match that static smtp banner?

PS: I don't want to end up in overwritten customization by Plesk Update ... since Plesk doesn't manage the hostname in postfix for different mail-servers.
 
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