Postfix /etc/postfix/main.cf

Authentic ๐Ÿ“‹ Debian 9 (Stretch) 45 lines

File Info

Size
45 lines
MD5
8802fc883e2a3c898c3fd49851bc53b2
SHA256
1b0560ab68c07b5cbb5297a5c5481d4e657312f07eda52d05d852a842a5cddc1

Quick Commands

curl:
curl https://exampleconfig.com/api/v1/config/original/8802fc883e2a3c898c3fd49851bc53b2?hint=main.cf
wget:
wget -O main.cf https://exampleconfig.com/api/v1/config/original/8802fc883e2a3c898c3fd49851bc53b2?hint=main.cf
/etc/postfix/main.cf
# See /usr/share/postfix/main.cf.dist for a commented, more complete version


# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name (Debian/GNU)
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = no

# See http://www.postfix.org/COMPATIBILITY_README.html -- default to 2 on
# fresh installs.
compatibility_level = 2

# TLS parameters
smtpd_tls_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
smtpd_tls_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
smtpd_use_tls=yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
myhostname = b012e090f537
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
mydestination = $myhostname, b012e090f537, localhost.localdomain, , localhost
relayhost = 
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all

How to Install Postfix

Alpine Linux

sudo apk add postfix

Debian

sudo apt update && sudo apt install postfix

Red Hat Enterprise Linux

sudo yum install postfix

Ubuntu

sudo apt update && sudo apt install postfix

Configuration File Location

File Path
/etc/postfix/main.cf
Directory
/etc/postfix/
Significance
System-wide configuration directory
Description
Files in /etc/ contain system-wide configuration settings that affect all users.

Complete Postfix Configuration Guide

What is main.cf?
Download the original 'main.cf' (main.cf) configuration file from a fresh Postfix installation on Debian 9 (Stretch). This is the factory-default mail server configuration, essential for email system recovery, anti-spam setup, and understanding secure mail relay settings.
Technical Details
Located at '/etc/postfix/main.cf', this 45-line file controls SMTP authentication, TLS encryption, spam filtering, mail routing, and delivery policies. Powers email infrastructure for millions of domains and handles everything from personal mail servers to enterprise email systems processing thousands of messages daily.
Common Configuration Question
How do you configure Postfix for secure mail delivery, spam prevention, and high availability on Debian 9?
Why Use This Configuration?
This default configuration includes SPF/DKIM support, TLS encryption, and anti-spam measures. Critical for email administrators, system administrators, and DevOps engineers managing production mail infrastructure.

Frequently Asked Questions

When should I use this main.cf file?

Use this original configuration file when you need to restore Postfix to its default state after misconfiguration, during fresh installations, or as a baseline for customization. It's particularly useful for troubleshooting when your current config isn't working properly.

How do I restore Postfix to default settings?

Download this file and replace your current configuration at /etc/postfix/main.cf. Make sure to backup your existing configuration first, then restart the Postfix service to apply the changes.

Is this main.cf file secure for production use?

This is the factory-default configuration that ships with Postfix on Debian 9 (Stretch). While it provides a secure baseline, you should review and customize security settings based on your specific production requirements and compliance needs.

What's the difference between this and other OS versions?

This configuration is specifically from Debian 9 (Stretch). Different operating systems and versions may have slightly different default settings, security patches, or feature availability. Check the compatibility section above for other OS versions.

Can I use this configuration file for Postfix troubleshooting?

Yes, this original configuration is excellent for troubleshooting. Compare it with your current settings to identify modifications that might be causing issues, or temporarily replace your config with this one to isolate problems.