I want to reject mail from spam sources aimed to my domains (local delivery) specified in:
virtual_mailbox_domains = example2.com, example3.net
All mail with a destination to example2.com and example3.net is delivered locally.
If any of the users in example2.com and/or example3.net want to use Postfix to relay mail (eg: to hotmail or yahoo mail)will have to authenticate first (SASL), if authentication is successful they are granted permission to relay mail.
Now, as I said first I want to reject mail aimed to example2.com and/or example3.net from spam sources
.(I know there could be other methods, but this thread is about smtpd_sender_restrictions vs smtpd_recipient_restrictions vs smtpd_client_restriction
I seen some settings that indicate setting smtpd_recipient_restrictions
to block spam sources (http://www.howtoforge.com/block_spam..._level_postfix
But for my goal, shouldn't I use smtpd_sender_restrictions
) or smtpd_client_restriction
, as stated in Postfix website, filters mails based on the MAIL FROM
command; This command is easy faked by telneting an open relay and typing in this command, therefore mail cound be sent with a valid MAIL FROM address, for this reason smtpd_sender_restrictions
does not seem to be my solution.
The only option left in my hypothesis is to use smtpd_client_restrictions
, which for my understanding checks the hostname or IP address of the smtpd client (the other MTA/SMTP connecting to my local smtpd(Postfix) ) in a black list, if listed mail is denied.
Am I correct here ?