Question DNSBL settings in Plesk Email Security vs general mail server settings?

[jnthn]

Server operating system version

AlmaLinux 10.1

Plesk version and microupdate number

18.0.77

In the settings of the Plesk Email Security extension, in the "Server Settings" tab under the "Advanced" section, is a setting titled "DNSBL" where I can enable various DNS block lists:
How does this relate to the general "Mail Server Settings" / "Server-wide mail settings", which in the "Settings" tab has a setting titled "Spam protection based on DNS blackhole lists"?

Do they have the same function? Would it be best to disable the general setting when I'm using the Plesk Email Security extension?

In general, I haven't been able to find technical documentation about the Plesk Email Security extension and its settings. This would be much appreciated, especially since it's a paid extension.

 

[Sebahat.hadzhi]

I believe the main difference is that you have the DNS Blackhole lists preconfigured in Plesk Email Security, contrarily to having to manually configure them in the server-wide mail settings, but I will double-check with our team to be certain and will follow-up.

 

[jnthn]

@Sebahat.hadzhi Do you have more info from the team about this already?

In the meantime, I did some more digging myself. One difference I noticed is that the DNSBL setting from the generic "Mail Server Settings" seems to be used in Postfix, while the one from "Plesk Email Security" is not.

I would guess the DNSBL setting from "Plesk Email Security" is applied to Amavis, which means it doesn't cause hard rejections, but it's used in a wider spam classification score. But it would be great to get some specific insight into it from the team, so we know for sure

 

[Sebahat.hadzhi]

Hi, @jnthn . Apologies for the delayed response. The update I got from our team internally confirms that there is no difference in terms of functionality and the main difference is that you have the DNS Blackhole lists preconfigured in Plesk Email Security.

 

[jnthn]

@Sebahat.hadzhi Clear, thanks!

I did notice some difference between them:

[…]

In the meantime, I did some more digging myself. One difference I noticed is that the DNSBL setting from the generic "Mail Server Settings" seems to be used in Postfix, while the one from "Plesk Email Security" is not.

I would guess the DNSBL setting from "Plesk Email Security" is applied to Amavis, which means it doesn't cause hard rejections, but it's used in a wider spam classification score. But it would be great to get some specific insight into it from the team, so we know for sure

It's OK for now, I know enough. But it may be nice to document this feature a bit better, to provide more insight into its working.