The Postfix Configuration File FormatConfiguration ParametersLocal Pathname InformationQueue and Process OwnershipThe mail_ownerdefault_privsInternet Host and Domain Namesmyhostname and mydomainSending MailmyoriginReceiving Mailinet_interfacesmydestinationmynetworksmynetworks_styleConnecting to Internet or Intranet Serversrelay_hostRejecting Unknown Local Userslocal_recipient_maps“User not found” Optionsrelocated_mapsAddress Rewritingallow_percent_hack, append_at_myorigin, append_dot_mydomainempty_address_recipientmasquerade_domains, masquerade_exceptionsswap_bangpathcanonical_mapsVirtual Domainsvirtual_mapsTransport Maptransport_mapsAlias Databasealias_mapsalias_databaseallow_mail_to_commands, allow_mail_to_filesAddress Extensionsrecipient_delimiterMailbox Deliveryhome_mailboxmailbox_commandmailbox_transport, fallback_transportluser_relayUCE Controlsheader_checksFast ETRN Servicefast_flush_policySMTP Greeting Bannersmtpd_bannerParallel Delivery to the Same Destinationinitial_destination_concurrencydefault_destination_concurrency_limitlocal_destination_concurrency_limitdefault_destination_recipient_limitDebugging Controldebug_peer_list, debug_peer_leveldebug_commandPlacing Limits on Objectsmessage_size_limitline_length_limitheader_size_limitDisplaying and Modifying Configuration ParametersSummary