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# 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_tls_cert_file=/etc/letsencrypt/live/<subdomain.domain.tld>/fullchain.pem
smtpd_tls_key_file=/etc/letsencrypt/live/<subdomain.domain.tld>/privkey.pem
smtpd_tls_security_level=may
smtpd_tls_protocols = !SSLv2, !SSLv3 !TLSv1
smtpd_tls_loglevel = 1

smtp_tls_CApath=/etc/ssl/certs
smtp_tls_security_level=may
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache


smtpd_relay_restrictions = permit_mynetworks permit_sasl_authenticated defer_unauth_destination
myhostname = <subdomain.domain.tld>
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination = $myhostname, <subdomain.domain.tld>, localhost.domain.tld, localhost
relayhost =
#mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1] <IP block of secondary MX> <IP block of primary MX>/29

mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
inet_protocols = all
maximal_queue_lifetime = 10d

# Allowed addresses
relay_recipient_maps = hash:/etc/postfix/relay_recipients

# Allowed domains
relay_domains = <comma-delimited list of domains on a single line>