December 2003
Beginner
278 pages
10h 47m
English
Content preview from Postfix: The Definitive GuideBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Postfix Anti-Spam Example
Now that we’ve covered the many aspects of Postfix’s anti-spam arsenal, we’ll finish with an example configuration. Requirements vary considerably from site to site, so it’s impossible to make actual recommendations apart from the considerations that have been discussed in this chapter. Example 11-2 can provide a starting point, but you must decide for yourself which restrictions fit your own circumstances.
Example 11-2. Sample restrictions to block UBE
smtpd_restriction_classes =
spamlover
spamhater
spamhater =
reject_invalid_hostname
reject_non_fqdn_hostname
reject_unknown_sender_domain
reject_rbl_client nospam.example.com
spamlover = permit
smtpd_helo_required = yes
smtpd_client_restrictions =
check_client_access hash:/etc/postfix/client_access
smtpd_helo_restrictions =
reject_invalid_hostname
check_helo_access hash:/etc/postfix/helo_access
smtpd_sender_restrictions =
reject_non_fqdn_sender
reject_unknown_sender_domain
check_sender_access hash:/etc/postfix/sender_access
smtpd_recipient_restrictions =
permit_mynetworks
reject_unauth_destination
reject_non_fqdn_recipient
reject_unknown_recipient_domain
smtpd_data_restrictions =
reject_unauth_pipelining
header_checks = /etc/postfix/header_checks
body_checks = /etc/postfix/body_checksYou should enter IP and email addresses into the access tables
from messages you receive that you have identified as spam. It’s very
difficult to block a lot of spam with the check_helo_access and check_sender_access restrictions ...
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I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.