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######################################################################
# MAIN CONFIGURATION SETTINGS #
######################################################################
#
# Specify your host's canonical name here. This should normally be the fully
# qualified "official" name of your host. If this option is not set, the
# uname() function is called to obtain the name. In many cases this does
# the right thing and you need not set anything explicitly.
primary_hostname =
SHORT_HOSTNAME =
# The next three settings create two lists of domains and one list of hosts.
# These lists are referred to later in this configuration using the syntax
# +local_domains, +relay_to_domains, and +relay_from_hosts, respectively. They
# are all colon-separated lists:
domainlist local_domains = @
domainlist relay_to_domains =
hostlist relay_from_hosts = localhost
# (We rely upon hostname resolution working for localhost, because the default
# uncommented configuration needs to work in IPv4-only environments.)
# Most straightforward access control requirements can be obtained by
# appropriate settings of the above options. In more complicated situations,
# you may need to modify the Access Control Lists (ACLs) which appear later in
# this file.
# The first setting specifies your local domains, for example:
#
# domainlist local_domains = my.first.domain : my.second.domain
#
# You can use "@" to mean "the name of the local host", as in the default
# setting above. This is the name that is specified by primary_hostname,
# as specified above (or defaulted). If you do not want to do any local
# deliveries, remove the "@" from the setting above. If you want to accept mail
# addressed to your host's literal IP address, for example, mail addressed to
# "user@[192.168.23.44]", you can add "@[]" as an item in the local domains
# list. You also need to uncomment "allow_domain_literals" below. This is not
# recommended for today's Internet.
# The second setting specifies domains for which your host is an incoming relay.
# If you are not doing any relaying, you should leave the list empty. However,
# if your host is an MX backup or gateway of some kind for some domains, you
# must set relay_to_domains to match those domains. For example:
#
# domainlist relay_to_domains = *.myco.com : my.friend.org
#
# This will allow any host to relay through your host to those domains.
# See the section of the manual entitled "Control of relaying" for more
# information.
# The third setting specifies hosts that can use your host as an outgoing relay
# to any other host on the Internet. Such a setting commonly refers to a
# complete local network as well as the localhost. For example:
#
# hostlist relay_from_hosts = <; 127.0.0.1 ; ::1 ; 192.168.0.0/16
#
# The "/16" is a bit mask (CIDR notation), not a number of hosts. Note that you
# have to include 127.0.0.1 if you want to allow processes on your host to send
# SMTP mail by using the loopback address. A number of MUAs use this method of
# sending mail. Often, connections are made to "localhost", which might be ::1
# on IPv6-enabled hosts. Do not forget CIDR for your IPv6 networks.
# All three of these lists may contain many different kinds of item, including
# wildcarded names, regular expressions, and file lookups. See the reference
# manual for details. The lists above are used in the access control lists for
# checking incoming messages. The names of these ACLs are defined here:
acl_smtp_rcpt = ${if ={587}{$interface_port} {acl_mua_rcpt} {acl_mta_rcpt}}
acl_smtp_mail = ${if ={587}{$interface_port} {acl_mua_mail} {accept}}
acl_smtp_data = ${if ={587}{$interface_port} {acl_mua_data} {acl_mta_data}}
acl_smtp_dkim = acl_mta_dkim
# You should not change those settings until you understand how ACLs work.
# If you are running a version of Exim that was compiled with the content-
# scanning extension, you can cause incoming messages to be automatically
# scanned for viruses. You have to modify the configuration in two places to
# set this up. The first of them is here, where you define the interface to
# your scanner. This example is typical for ClamAV; see the manual for details
# of what to set for other virus scanners. The second modification is in the
# acl_check_data access control list (see below).
# av_scanner = clamd:/run/clamav/clamd.sock
# For spam scanning, there is a similar option that defines the interface to
# SpamAssassin. You do not need to set this if you are using the default, which
# is shown in this commented example. As for virus scanning, you must also
# modify the acl_check_data access control list to enable spam scanning.
# spamd_address = 127.0.0.1 783
# spamd_address = 127.0.0.1 11333 variant=rspamd
# If Exim is compiled with support for TLS, you may want to enable the
# following options so that Exim allows clients to make encrypted
# connections. In the authenticators section below, there are template
# configurations for plaintext username/password authentication. This kind
# of authentication is only safe when used within a TLS connection, so the
# authenticators will only work if the following TLS settings are turned on
# as well.
# Allow any client to use TLS.
tls_advertise_hosts = *
# Specify the location of the Exim server's TLS certificate and private key.
# The private key must not be encrypted (password protected). You can put
# the certificate and private key in the same file, in which case you only
# need the first setting, or in separate files, in which case you need both
# options.
tls_certificate = CERTDIR/$primary_hostname.crt
tls_privatekey = CERTDIR/$primary_hostname.pem
# In order to support roaming users who wish to send email from anywhere,
# you may want to make Exim listen on other ports as well as port 25, in
# case these users need to send email from a network that blocks port 25.
# The standard port for this purpose is port 587, the "message submission"
# port. See RFC 4409 for details. Microsoft MUAs cannot be configured to
# talk the message submission protocol correctly, so if you need to support
# them you should also allow TLS-on-connect on the traditional but
# non-standard port 465.
daemon_smtp_ports = 25 : 587
# tls_on_connect_ports = 465
# Specify the domain you want to be added to all unqualified addresses
# here. An unqualified address is one that does not contain an "@" character
# followed by a domain. For example, "caesar@rome.example" is a fully qualified
# address, but the string "caesar" (i.e. just a login name) is an unqualified
# email address. Unqualified addresses are accepted only from local callers by
# default. See the recipient_unqualified_hosts option if you want to permit
# unqualified addresses from remote sources. If this option is not set, the
# primary_hostname value is used for qualification.
# qualify_domain =
# If you want unqualified recipient addresses to be qualified with a different
# domain to unqualified sender addresses, specify the recipient domain here.
# If this option is not set, the qualify_domain value is used.
# qualify_recipient =
# The following line must be uncommented if you want Exim to recognize
# addresses of the form "user@[10.11.12.13]" that is, with a "domain literal"
# (an IP address) instead of a named domain. The RFCs still require this form,
# but it makes little sense to permit mail to be sent to specific hosts by
# their IP address in the modern Internet. This ancient format has been used
# by those seeking to abuse hosts by using them for unwanted relaying. If you
# really do want to support domain literals, uncomment the following line, and
# see also the "domain_literal" router below.
# allow_domain_literals
# No deliveries will ever be run under the uids of users specified by
# never_users (a colon-separated list). An attempt to do so causes a panic
# error to be logged, and the delivery to be deferred. This is a paranoic
# safety catch. There is an even stronger safety catch in the form of the
# FIXED_NEVER_USERS setting in the configuration for building Exim. The list of
# users that it specifies is built into the binary, and cannot be changed. The
# option below just adds additional users to the list. The default for
# FIXED_NEVER_USERS is "root", but just to be absolutely sure, the default here
# is also "root".
# Note that the default setting means you cannot deliver mail addressed to root
# as if it were a normal user. This isn't usually a problem, as most sites have
# an alias for root that redirects such mail to a human administrator.
never_users = root
# The setting below causes Exim to do a reverse DNS lookup on all incoming
# IP calls, in order to get the true host name. If you feel this is too
# expensive, you can specify the networks for which a lookup is done, or
# remove the setting entirely.
host_lookup = *
# The settings below cause Exim to make RFC 1413 (ident) callbacks
# for all incoming SMTP calls. You can limit the hosts to which these
# calls are made, and/or change the timeout that is used. If you set
# the timeout to zero, all RFC 1413 calls are disabled. RFC 1413 calls
# are cheap and can provide useful information for tracing problem
# messages, but some hosts and firewalls have problems with them.
# This can result in a timeout instead of an immediate refused
# connection, leading to delays on starting up SMTP sessions.
# (The default was reduced from 30s to 5s for release 4.61. and to
# disabled for release 4.86)
#
rfc1413_hosts = *
rfc1413_query_timeout = 5s
# Enable an efficiency feature. We advertise the feature; clients
# may request to use it. For multi-recipient mails we then can
# reject or accept per-user after the message is received.
#
prdr_enable = true
# By default, Exim expects all envelope addresses to be fully qualified, that
# is, they must contain both a local part and a domain. If you want to accept
# unqualified addresses (just a local part) from certain hosts, you can specify
# these hosts by setting one or both of
#
# sender_unqualified_hosts =
# recipient_unqualified_hosts =
#
# to control sender and recipient addresses, respectively. When this is done,
# unqualified addresses are qualified using the settings of qualify_domain
# and/or qualify_recipient (see above).
# Unless you run a high-volume site you probably want more logging
# detail than the default. Adjust to suit.
log_selector = +smtp_protocol_error +smtp_syntax_error +tls_certificate_verified
# If you want Exim to support the "percent hack" for certain domains,
# uncomment the following line and provide a list of domains. The "percent
# hack" is the feature by which mail addressed to x%y@z (where z is one of
# the domains listed) is locally rerouted to x@y and sent on. If z is not one
# of the "percent hack" domains, x%y is treated as an ordinary local part. This
# hack is rarely needed nowadays; you should not enable it unless you are sure
# that you really need it.
#
# percent_hack_domains =
#
# As well as setting this option you will also need to remove the test
# for local parts containing % in the ACL definition below.
# When Exim can neither deliver a message nor return it to sender, it "freezes"
# the delivery error message (aka "bounce message"). There are also other
# circumstances in which messages get frozen. They will stay on the queue for
# ever unless one of the following options is set.
# This option unfreezes frozen bounce messages after two days, tries
# once more to deliver them, and ignores any delivery failures.
ignore_bounce_errors_after = 2d
# This option cancels (removes) frozen messages that are older than a week.
timeout_frozen_after = 7d
# By default, messages that are waiting on Exim's queue are all held in a
# single directory called "input" which it itself within Exim's spool
# directory. (The default spool directory is specified when Exim is built, and
# is often /var/spool/exim/.) Exim works best when its queue is kept short, but
# there are circumstances where this is not always possible. If you uncomment
# the setting below, messages on the queue are held in 62 subdirectories of
# "input" instead of all in the same directory. The subdirectories are called
# 0, 1, ... A, B, ... a, b, ... z. This has two benefits: (1) If your file
# system degrades with many files in one directory, this is less likely to
# happen; (2) Exim can process the queue one subdirectory at a time instead of
# all at once, which can give better performance with large queues.
# split_spool_directory = true
# If you're in a part of the world where ASCII is not sufficient for most
# text, then you're probably familiar with RFC2047 message header extensions.
# By default, Exim adheres to the specification, including a limit of 76
# characters to a line, with encoded words fitting within a line.
# If you wish to use decoded headers in message filters in such a way
# that successful decoding of malformed messages matters, you may wish to
# configure Exim to be more lenient.
#
# check_rfc2047_length = false
#
# In particular, the Exim maintainers have had multiple reports of problems
# from Russian administrators of issues until they disable this check,
# because of some popular, yet buggy, mail composition software.
# If you wish to be strictly RFC compliant, or if you know you'll be
# exchanging email with systems that are not 8-bit clean, then you may
# wish to disable advertising 8BITMIME. Uncomment this option to do so.
# accept_8bitmime = false
# Exim does not make use of environment variables itself. However,
# libraries that Exim uses (e.g. LDAP) depend on specific environment settings.
# There are two lists: keep_environment for the variables we trust, and
# add_environment for variables we want to set to a specific value.
# Note that TZ is handled separateley by the timezone runtime option
# and TIMEZONE_DEFAULT buildtime option.
# keep_environment = ^LDAP
# add_environment = PATH=/usr/bin::/bin
# LMTP backend
LMTP_BACKENDS =
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