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Issue Problem with reverse DNS (SMTP Banner) for multiple Domains

frankyab

New Pleskian
Hello everyone,

currently I struggle with the SMTP Banner. on mxtoolbox. I get the error Reverse DNS does not match SMTP Banner

The plesk/mail setup is as follows.

domain1.com is the main domain and also the hostname for the plesk server. Here everything is correct SMTP Banner is working
domain2.com, smtp banner error
domain3.com, smtp banner error

All 3 Domains have dedicated IP's to them. Reverse DNS entries are set and so far all working, DKIM, SPF records also set and working. Only the SMTP Banner Chek is not working for domain2 and domain3

In the plesk server settings I've set for the outgoing mail mode: Send from domain IP addresses and use domain names in SMTP greeting, that should be the correct method or am I wrong?

Hope someone can point me in the right direction
 
By default, Postfix will show the hostname of the server in the SMTP banner. In most cases that's perfectly fine and will not cause any problems (despite mxtoolbox complaining about it), as long as the hostname in the SMTP banner can be resolved. So in my opinion you can ignore that.

Plesk does not come with a built-in functionality to change the SMTP banner per IP address, but there is a workaround:
 
By default, Postfix will show the hostname of the server in the SMTP banner. In most cases that's perfectly fine and will not cause any problems (despite mxtoolbox complaining about it), as long as the hostname in the SMTP banner can be resolved. So in my opinion you can ignore that.
Ok thank you for that information. So in general I should be fine? Don't want to go through the trouble of contacting every single provider because they put the domain on a blacklist because of a wrong SMTP Banner.
 
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