Question "Block email submissions except from one IP."

[maverik23]

Server operating system version

ubuntu 20.04

Plesk version and microupdate number

18.0.59

Hello, I'm facing the following issue.
I need all the email accounts on the server to only allow login if they are from a specific IP address, except for 3 accounts that can login from any IP.

How can I achieve this?
I tried modifying the blacklists.db but couldn't succeed.

 

[Peter Debik]

You could use the Plesk Firewall extension for it, e.g. deny all traffic for ports 993, 995, 110, 143 but for your one IP address. You can add more rules allowing specific IP addresses to pass (by changing the order of the rules, e.g. first allow what you want to allow, then block all that's left).

 

[maverik23]

Ok, I'm still trying with the configurations
Now I have the following configuration in main.cf

smtpd_client_restrictions =
    check_client_access hash:/etc/postfix/client_access

smtpd_recipient_restrictions =
    permit_mynetworks,
    permit_sasl_authenticated,
    reject_unauth_destination

smtpd_sasl_authenticated_header = yes

and in client_access

xxx.xxx.xxx.xxx OK

[email protected] OK
[email protected] OK
[email protected] OK

I ask because I am not an expert in servers and there are things I don't understand.
I don't know if that configuration does what I need or not.