RATS NoPtr in mxtoolbox and RCVD_IN_SORBS_WEB from SpamAssassin - how to set up a mail server correctly?

Question

Mail server

For a long time, I butted heads with VPS hosting technical support so that the mail server was configured correctly, and as a result, 2 problems remained

: shows errors - is it a glitch of the mxtoolbox.com service or is there really some kind of problem?

2) Next, I send a letter from the Thunderbird mail client in Mac OS to the address in mail-tester.com - and I see this thing:

SpamAssassin swears at the ip-address of my PC (and not the mail server) - how is it? I send mail through a mail server, why is my ip-address there, which can be anything (obviously "not white")

Answer 1

1. RATS NoPtr - this is not about the fact that you do not have a PTR record. This means that the IP of your mail server belongs to a pool of addresses from which the host that owns it allows sending mail without a PTR record. In general - a kind of blacklist.
2. Yes, some blacklists check not only the IP of the mail server, but also any other associated IP (for example, the domain, the actual sender, etc.).
What can be done ?
According to item 1 - to fumble the hoster so that he contacts the blacklist and convinces him of his fluffiness or change the IP to a clean one from another pool.
According to item 2 - configure the mail server so that it does not indicate the IP of your PC from which the client sends mail in the headers.

Answer 2

1. RATS NoPtr - this is not about the fact that you do not have a PTR record. This means that the IP of your mail server belongs to a pool of addresses from which the host that owns it allows sending mail without a PTR record. In general - a kind of blacklist.

is it not because our VPS hosts several domains (websites)?
and then the hoster just wrote something like:

each domain must have its own IP, and the corresponding PTR on it, so that there are no such errors

and there is?
I naturally checked the ip-address of the mail server against blacklists - it is clean, it is not listed anywhere!

According to item 1 - to fumble the hoster so that he contacts the blacklist and convinces him of his fluffiness or change the IP to a clean one from another pool.

so, the ip-address of the mail server (domain/site) is clean, not in the blacklist!

According to item 2 - configure the mail server so that it does not indicate the IP of your PC from which the client sends mail in the headers.

technical support specialists do not know how to do this, we found something on this topic, it seems to us here: https://serverfault.com/questions/845504/spamassas... - they made the settings - but it did not help!

Answer 3

According to item 2, go to the sorbs.net website, read what is written there, follow the recommendations. Getting into sorbs is an unpleasant thing, but tolerable, the main thing is not to bruise and not say that only the MTS logo is cooler than you :)