Provided by: postfix_2.2.10-1_i386 bug

NAME

       smtpd - Postfix SMTP server

SYNOPSIS

       smtpd [generic Postfix daemon options]

DESCRIPTION

       The  SMTP  server accepts network connection requests and performs zero
       or more SMTP transactions per connection.   Each  received  message  is
       piped  through  the  cleanup(8) daemon, and is placed into the incoming
       queue as one single queue  file.   For  this  mode  of  operation,  the
       program expects to be run from the master(8) process manager.

       Alternatively,  the  SMTP  server  takes  an  established connection on
       standard input and deposits messages directly into the maildrop  queue.
       In  this  so-called  stand-alone  mode, the SMTP server can accept mail
       even while the mail system is not running.

       The SMTP  server  implements  a  variety  of  policies  for  connection
       requests,  and  for parameters given to HELO, ETRN, MAIL FROM, VRFY and
       RCPT  TO  commands.  They  are  detailed  below  and  in  the   main.cf
       configuration file.

SECURITY

       The  SMTP  server  is  moderately  security-sensitive. It talks to SMTP
       clients and to DNS servers on the network. The SMTP server can  be  run
       chrooted at fixed low privilege.

STANDARDS

       RFC 821 (SMTP protocol)
       RFC 1123 (Host requirements)
       RFC 1652 (8bit-MIME transport)
       RFC 1869 (SMTP service extensions)
       RFC 1870 (Message Size Declaration)
       RFC 1985 (ETRN command)
       RFC 2554 (AUTH command)
       RFC 2821 (SMTP protocol)
       RFC 2920 (SMTP Pipelining)
       RFC 3207 (STARTTLS command)

DIAGNOSTICS

       Problems and transactions are logged to syslogd(8).

       Depending   on   the  setting  of  the  notify_classes  parameter,  the
       postmaster  is  notified  of   bounces,   protocol   problems,   policy
       violations, and of other trouble.

CONFIGURATION PARAMETERS

       Changes  to  main.cf are picked up automatically, as smtpd(8) processes
       run for only a limited amount of time. Use the command "postfix reload"
       to speed up a change.

       The  text  below provides only a parameter summary. See postconf(5) for
       more details including examples.

COMPATIBILITY CONTROLS

       The following parameters work around  implementation  errors  in  other
       software,  and/or  allow  you to override standards in order to prevent
       undesirable use.

       broken_sasl_auth_clients (no)
              Enable inter-operability with SMTP  clients  that  implement  an
              obsolete version of the AUTH command (RFC 2554).

       disable_vrfy_command (no)
              Disable the SMTP VRFY command.

       smtpd_noop_commands (empty)
              List  of  commands  that the Postfix SMTP server replies to with
              "250 Ok", without doing any syntax checks and  without  changing
              state.

       strict_rfc821_envelopes (no)
              Require  that  addresses  received in SMTP MAIL FROM and RCPT TO
              commands are enclosed with <>, and that those addresses  do  not
              contain RFC 822 style comments or phrases.

       Available in Postfix version 2.1 and later:

       resolve_null_domain (no)
              Resolve  an  address  that ends in the "@" null domain as if the
              local hostname were specified, instead of rejecting the  address
              as invalid.

       smtpd_reject_unlisted_sender (no)
              Request  that  the Postfix SMTP server rejects mail from unknown
              sender addresses, even when no  explicit  reject_unlisted_sender
              access restriction is specified.

       smtpd_sasl_exceptions_networks (empty)
              What SMTP clients Postfix will not offer AUTH support to.

       Available in Postfix version 2.2 and later:

       smtpd_discard_ehlo_keyword_address_maps (empty)
              Lookup  tables,  indexed by the remote SMTP client address, with
              case insensitive lists of EHLO keywords  (pipelining,  starttls,
              auth,  etc.)  that  the  SMTP  server  will not send in the EHLO
              response to a remote SMTP client.

       smtpd_discard_ehlo_keywords (empty)
              A case insensitive list of EHLO keywords (pipelining,  starttls,
              auth,  etc.)  that  the  SMTP  server  will not send in the EHLO
              response to a remote SMTP client.

ADDRESS REWRITING CONTROLS

       See the ADDRESS_REWRITING_README document for a detailed discussion  of
       Postfix address rewriting.

       receive_override_options (empty)
              Enable   or   disable  recipient  validation,  built-in  content
              filtering, or address mapping.

       Available in Postfix version 2.2 and later:

       local_header_rewrite_clients (permit_inet_interfaces)
              Rewrite message header addresses in mail from these clients  and
              update incomplete addresses with the domain name in $myorigin or
              $mydomain; either  don’t  rewrite  message  headers  from  other
              clients at all, or rewrite message headers and update incomplete
              addresses    with    the     domain     specified     in     the
              remote_header_rewrite_domain parameter.

AFTER QUEUE EXTERNAL CONTENT INSPECTION CONTROLS

       As  of  version  1.0,  Postfix can be configured to send new mail to an
       external content filter AFTER the mail is queued. This  content  filter
       is  expected  to  inject  mail  back  into a (Postfix or other) MTA for
       further delivery. See the FILTER_README document for details.

       content_filter (empty)
              The name of a mail delivery transport that filters mail after it
              is queued.

BEFORE QUEUE EXTERNAL CONTENT INSPECTION CONTROLS

       As  of  version  2.1, the Postfix SMTP server can be configured to send
       incoming mail to a real-time SMTP-based content filter BEFORE  mail  is
       queued.   This  content  filter  is  expected  to inject mail back into
       Postfix.  See the SMTPD_PROXY_README document for  details  on  how  to
       configure and operate this feature.

       smtpd_proxy_filter (empty)
              The hostname and TCP port of the mail filtering proxy server.

       smtpd_proxy_ehlo ($myhostname)
              How  the  Postfix  SMTP  server  announces  itself  to the proxy
              filter.

       smtpd_proxy_timeout (100s)
              The time limit for connecting to a proxy filter and for  sending
              or receiving information.

GENERAL CONTENT INSPECTION CONTROLS

       The  following parameters are applicable for both built-in and external
       content filters.

       Available in Postfix version 2.1 and later:

       receive_override_options (empty)
              Enable  or  disable  recipient  validation,   built-in   content
              filtering, or address mapping.

EXTERNAL CONTENT INSPECTION CONTROLS

       The  following  parameters  are  applicable  for  both before-queue and
       after-queue content filtering.

       Available in Postfix version 2.1 and later:

       smtpd_authorized_xforward_hosts (empty)
              What SMTP clients are allowed to use the XFORWARD feature.

SASL AUTHENTICATION CONTROLS

       Postfix SASL support (RFC 2554) can be used to authenticate remote SMTP
       clients  to  the  Postfix  SMTP server, and to authenticate the Postfix
       SMTP client to a remote SMTP server.  See the SASL_README document  for
       details.

       broken_sasl_auth_clients (no)
              Enable  inter-operability  with  SMTP  clients that implement an
              obsolete version of the AUTH command (RFC 2554).

       smtpd_sasl_auth_enable (no)
              Enable SASL authentication in the Postfix SMTP server.

       smtpd_sasl_application_name (smtpd)
              The application name used for SASL server initialization.

       smtpd_sasl_local_domain (empty)
              The name of the local SASL authentication realm.

       smtpd_sasl_security_options (noanonymous)
              Restrict what authentication mechanisms the Postfix SMTP  server
              will offer to the client.

       smtpd_sender_login_maps (empty)
              Optional  lookup table with the SASL login names that own sender
              (MAIL FROM) addresses.

       Available in Postfix version 2.1 and later:

       smtpd_sasl_exceptions_networks (empty)
              What SMTP clients Postfix will not offer AUTH support to.

STARTTLS SUPPORT CONTROLS

       Detailed information about STARTTLS configuration may be found  in  the
       TLS_README document.

       smtpd_use_tls (no)
              Opportunistic  mode:  announce STARTTLS support to SMTP clients,
              but do not require that clients use TLS encryption.

       smtpd_enforce_tls (no)
              Enforcement mode: announce STARTTLS support to SMTP clients, and
              require that clients use TLS encryption.

       smtpd_sasl_tls_security_options ($smtpd_sasl_security_options)
              The  SASL  authentication security options that the Postfix SMTP
              server uses for TLS encrypted SMTP sessions.

       smtpd_starttls_timeout (300s)
              The time limit for Postfix SMTP server write and read operations
              during TLS startup and shutdown handshake procedures.

       smtpd_tls_CAfile (empty)
              The  file  with  the  certificate of the certification authority
              (CA) that issued the Postfix SMTP server certificate.

       smtpd_tls_CAfile (empty)
              The file with the certificate  of  the  certification  authority
              (CA) that issued the Postfix SMTP server certificate.

       smtpd_tls_ask_ccert (no)
              Ask a remote SMTP client for a client certificate.

       smtpd_tls_auth_only (no)
              When  TLS  encryption is optional in the Postfix SMTP server, do
              not announce or  accept  SASL  authentication  over  unencrypted
              connections.

       smtpd_tls_ccert_verifydepth (5)
              The verification depth for remote SMTP client certificates.

       smtpd_tls_cert_file (empty)
              File with the Postfix SMTP server RSA certificate in PEM format.

       smtpd_tls_cipherlist (empty)
              Controls the Postfix SMTP server TLS cipher selection scheme.

       smtpd_tls_dcert_file (empty)
              File with the Postfix SMTP server DSA certificate in PEM format.

       smtpd_tls_dh1024_param_file (empty)
              File  with DH parameters that the Postfix SMTP server should use
              with EDH ciphers.

       smtpd_tls_dh512_param_file (empty)
              File with DH parameters that the Postfix SMTP server should  use
              with EDH ciphers.

       smtpd_tls_dkey_file ($smtpd_tls_dcert_file)
              File with the Postfix SMTP server DSA private key in PEM format.

       smtpd_tls_key_file ($smtpd_tls_cert_file)
              File with the Postfix SMTP server RSA private key in PEM format.

       smtpd_tls_loglevel (0)
              Enable additional Postfix SMTP server logging of TLS activity.

       smtpd_tls_received_header (no)
              Request that the Postfix SMTP server produces Received:  message
              headers that include information about the protocol  and  cipher
              used,  as  well  as the client CommonName and client certificate
              issuer CommonName.

       smtpd_tls_req_ccert (no)
              When TLS encryption is enforced, require a  remote  SMTP  client
              certificate in order to allow TLS connections to proceed.

       smtpd_tls_session_cache_database (empty)
              Name of the file containing the optional Postfix SMTP server TLS
              session cache.

       smtpd_tls_session_cache_timeout (3600s)
              The expiration time of Postfix SMTP  server  TLS  session  cache
              information.

       smtpd_tls_wrappermode (no)
              Run  the Postfix SMTP server in the non-standard "wrapper" mode,
              instead of using the STARTTLS command.

       tls_daemon_random_bytes (32)
              The number of pseudo-random bytes that an  smtp(8)  or  smtpd(8)
              process  requests from the tlsmgr(8) server in order to seed its
              internal pseudo random number generator (PRNG).

VERP SUPPORT CONTROLS

       With VERP style delivery,  each  recipient  of  a  message  receives  a
       customized  copy  of  the  message  with  his/her own recipient address
       encoded in the envelope sender address.  The VERP_README file describes
       configuration  and  operation  details  of Postfix support for variable
       envelope return path addresses.  VERP style delivery is requested  with
       the  SMTP  XVERP  command or with the "sendmail -V" command-line option
       and is available in Postfix version 1.1 and later.

       default_verp_delimiters (+=)
              The two default VERP delimiter characters.

       verp_delimiter_filter (-=+)
              The characters Postfix accepts as VERP delimiter  characters  on
              the Postfix sendmail(1) command line and in SMTP commands.

       Available in Postfix version 1.1 and 2.0:

       authorized_verp_clients ($mynetworks)
              What SMTP clients are allowed to specify the XVERP command.

       Available in Postfix version 2.1 and later:

       smtpd_authorized_verp_clients ($authorized_verp_clients)
              What SMTP clients are allowed to specify the XVERP command.

TROUBLE SHOOTING CONTROLS

       The  DEBUG_README  document describes how to debug parts of the Postfix
       mail system. The methods vary from making the software  log  a  lot  of
       detail, to running some daemon processes under control of a call tracer
       or debugger.

       debug_peer_level (2)
              The increment in verbose logging level when a remote  client  or
              server matches a pattern in the debug_peer_list parameter.

       debug_peer_list (empty)
              Optional  list  of  remote  client or server hostname or network
              address  patterns  that  cause  the  verbose  logging  level  to
              increase by the amount specified in $debug_peer_level.

       error_notice_recipient (postmaster)
              The  recipient  of  postmaster notifications about mail delivery
              problems that  are  caused  by  policy,  resource,  software  or
              protocol errors.

       notify_classes (resource, software)
              The list of error classes that are reported to the postmaster.

       soft_bounce (no)
              Safety  net to keep mail queued that would otherwise be returned
              to the sender.

       Available in Postfix version 2.1 and later:

       smtpd_authorized_xclient_hosts (empty)
              What SMTP clients are allowed to use the XCLIENT feature.

KNOWN VERSUS UNKNOWN RECIPIENT CONTROLS

       As of Postfix version 2.0, the SMTP server  rejects  mail  for  unknown
       recipients.  This  prevents  the  mail  queue  from  clogging  up  with
       undeliverable MAILER-DAEMON messages. Additional  information  on  this
       topic   is   in  the  LOCAL_RECIPIENT_README  and  ADDRESS_CLASS_README
       documents.

       show_user_unknown_table_name (yes)
              Display the name of the recipient table in  the  "User  unknown"
              responses.

       canonical_maps (empty)
              Optional  address  mapping lookup tables for message headers and
              envelopes.

       recipient_canonical_maps (empty)
              Optional address mapping lookup tables for envelope  and  header
              recipient addresses.

       Parameters concerning known/unknown local recipients:

       mydestination ($myhostname, localhost.$mydomain, localhost)
              The  list of domains that are delivered via the $local_transport
              mail delivery transport.

       inet_interfaces (all)
              The network interface addresses that this mail  system  receives
              mail on.

       proxy_interfaces (empty)
              The  network  interface addresses that this mail system receives
              mail on by way of a proxy or network address translation unit.

       inet_protocols (ipv4)
              The Internet protocols Postfix will attempt to use  when  making
              or accepting connections.

       local_recipient_maps (proxy:unix:passwd.byname $alias_maps)
              Lookup tables with all names or addresses of local recipients: a
              recipient   address   is   local   when   its   domain   matches
              $mydestination, $inet_interfaces or $proxy_interfaces.

       unknown_local_recipient_reject_code (550)
              The numerical Postfix SMTP server response code when a recipient
              address is local, and $local_recipient_maps specifies a list  of
              lookup tables that does not match the recipient.

       Parameters concerning known/unknown recipients of relay destinations:

       relay_domains ($mydestination)
              What  destination  domains  (and subdomains thereof) this system
              will relay mail to.

       relay_recipient_maps (empty)
              Optional lookup tables with all valid addresses in  the  domains
              that match $relay_domains.

       unknown_relay_recipient_reject_code (550)
              The  numerical  Postfix  SMTP server reply code when a recipient
              address   matches   $relay_domains,   and   relay_recipient_maps
              specifies  a  list  of  lookup  tables  that  does not match the
              recipient address.

       Parameters  concerning  known/unknown  recipients  in   virtual   alias
       domains:

       virtual_alias_domains ($virtual_alias_maps)
              Postfix  is  final destination for the specified list of virtual
              alias domains, that is, domains  for  which  all  addresses  are
              aliased to addresses in other local or remote domains.

       virtual_alias_maps ($virtual_maps)
              Optional  lookup  tables  that  alias specific mail addresses or
              domains to other local or remote address.

       unknown_virtual_alias_reject_code (550)
              The SMTP server reply code  when  a  recipient  address  matches
              $virtual_alias_domains, and $virtual_alias_maps specifies a list
              of lookup tables that does not match the recipient address.

       Parameters  concerning  known/unknown  recipients  in  virtual  mailbox
       domains:

       virtual_mailbox_domains ($virtual_mailbox_maps)
              Postfix  is final destination for the specified list of domains;
              mail is  delivered  via  the  $virtual_transport  mail  delivery
              transport.

       virtual_mailbox_maps (empty)
              Optional  lookup  tables with all valid addresses in the domains
              that match $virtual_mailbox_domains.

       unknown_virtual_mailbox_reject_code (550)
              The SMTP server reply code  when  a  recipient  address  matches
              $virtual_mailbox_domains,  and $virtual_mailbox_maps specifies a
              list of lookup tables that does not match the recipient address.

RESOURCE AND RATE CONTROLS

       The following parameters limit resource usage by the SMTP server and/or
       control client request rates.

       line_length_limit (2048)
              Upon input, long lines are chopped up into  pieces  of  at  most
              this length; upon delivery, long lines are reconstructed.

       queue_minfree (0)
              The  minimal  amount  of  free  space in bytes in the queue file
              system that is needed to receive mail.

       message_size_limit (10240000)
              The maximal size in  bytes  of  a  message,  including  envelope
              information.

       smtpd_recipient_limit (1000)
              The  maximal  number  of recipients that the Postfix SMTP server
              accepts per message delivery request.

       smtpd_timeout (300s)
              The time limit for sending a Postfix SMTP  server  response  and
              for receiving a remote SMTP client request.

       smtpd_history_flush_threshold (100)
              The  maximal  number of lines in the Postfix SMTP server command
              history before it is flushed upon receipt of EHLO, RSET, or  end
              of DATA.

       The  per  SMTP  client  connection  count  and  request rate limits are
       implemented  in  co-operation  with  the  anvil(8)  service,  and   are
       available in Postfix version 2.2 and later.

       smtpd_client_connection_count_limit (50)
              How  many simultaneous connections any client is allowed to make
              to this service.

       smtpd_client_connection_rate_limit (0)
              The maximal number of connection attempts any client is  allowed
              to make to this service per time unit.

       smtpd_client_message_rate_limit (0)
              The  maximal number of message delivery requests that any client
              is allowed to make to this service per time unit, regardless  of
              whether or not Postfix actually accepts those messages.

       smtpd_client_recipient_rate_limit (0)
              The  maximal  number  of  recipient addresses that any client is
              allowed to send to this service per  time  unit,  regardless  of
              whether or not Postfix actually accepts those recipients.

       smtpd_client_event_limit_exceptions ($mynetworks)
              Clients  that  are  excluded  from  connection count, connection
              rate, or SMTP request rate restrictions.

TARPIT CONTROLS

       When a remote SMTP client makes errors, the  Postfix  SMTP  server  can
       insert  delays  before  responding. This can help to slow down run-away
       software.  The behavior is controlled by an error counter  that  counts
       the number of errors within an SMTP session that a client makes without
       delivering mail.

       smtpd_error_sleep_time (1s)
              With Postfix 2.1 and later: the SMTP server response delay after
              a  client has made more than $smtpd_soft_error_limit errors, and
              fewer than $smtpd_hard_error_limit  errors,  without  delivering
              mail.

       smtpd_soft_error_limit (10)
              The  number  of  errors  a remote SMTP client is allowed to make
              without delivering mail before the  Postfix  SMTP  server  slows
              down all its responses.

       smtpd_hard_error_limit (20)
              The  maximal number of errors a remote SMTP client is allowed to
              make without delivering mail.

       smtpd_junk_command_limit (100)
              The number of junk commands (NOOP, VRFY, ETRN or  RSET)  that  a
              remote  SMTP  client  can  send  before  the Postfix SMTP server
              starts to increment the error counter with each junk command.

       Available in Postfix version 2.1 and later:

       smtpd_recipient_overshoot_limit (1000)
              The number of recipients that a remote SMTP client can  send  in
              excess  of  the  limit  specified  with  $smtpd_recipient_limit,
              before the Postfix SMTP server increments the per-session  error
              count for each excess recipient.

ACCESS POLICY DELEGATION CONTROLS

       As  of version 2.1, Postfix can be configured to delegate access policy
       decisions to an external server that runs  outside  Postfix.   See  the
       file SMTPD_POLICY_README for more information.

       smtpd_policy_service_max_idle (300s)
              The  time after which an idle SMTPD policy service connection is
              closed.

       smtpd_policy_service_max_ttl (1000s)
              The time after which an active SMTPD policy  service  connection
              is closed.

       smtpd_policy_service_timeout (100s)
              The time limit for connecting to, writing to or receiving from a
              delegated SMTPD policy server.

ACCESS CONTROLS

       The SMTPD_ACCESS_README document gives an introduction to all the  SMTP
       server access control features.

       smtpd_delay_reject (yes)
              Wait    until    the   RCPT   TO   command   before   evaluating
              $smtpd_client_restrictions,     $smtpd_helo_restrictions     and
              $smtpd_sender_restrictions,  or  wait  until  the  ETRN  command
              before      evaluating      $smtpd_client_restrictions       and
              $smtpd_helo_restrictions.

       parent_domain_matches_subdomains (see β€β€™postconf -dβ€β€™ output)
              What   Postfix   features   match   subdomains  of  "domain.tld"
              automatically, instead of requiring  an  explicit  ".domain.tld"
              pattern.

       smtpd_client_restrictions (empty)
              Optional  SMTP  server  access  restrictions in the context of a
              client SMTP connection request.

       smtpd_helo_required (no)
              Require that a remote  SMTP  client  introduces  itself  at  the
              beginning of an SMTP session with the HELO or EHLO command.

       smtpd_helo_restrictions (empty)
              Optional  restrictions  that  the Postfix SMTP server applies in
              the context of the SMTP HELO command.

       smtpd_sender_restrictions (empty)
              Optional restrictions that the Postfix SMTP  server  applies  in
              the context of the MAIL FROM command.

       smtpd_recipient_restrictions                        (permit_mynetworks,
       reject_unauth_destination)
              The  access restrictions that the Postfix SMTP server applies in
              the context of the RCPT TO command.

       smtpd_etrn_restrictions (empty)
              Optional SMTP server access restrictions in  the  context  of  a
              client ETRN request.

       allow_untrusted_routing (no)
              Forward       mail       with      sender-specified      routing
              (user[@%!]remote[@%!]site)    from    untrusted    clients    to
              destinations matching $relay_domains.

       smtpd_restriction_classes (empty)
              User-defined aliases for groups of access restrictions.

       smtpd_null_access_lookup_key (<>)
              The  lookup  key  to be used in SMTP access(5) tables instead of
              the null sender address.

       permit_mx_backup_networks (empty)
              Restrict the use of the permit_mx_backup SMTP access feature  to
              only domains whose primary MX hosts match the listed networks.

       Available in Postfix version 2.0 and later:

       smtpd_data_restrictions (empty)
              Optional  access  restrictions  that  the  Postfix  SMTP  server
              applies in the context of the SMTP DATA command.

       smtpd_expansion_filter (see β€β€™postconf -dβ€β€™ output)
              What characters are allowed in $name  expansions  of  RBL  reply
              templates.

       Available in Postfix version 2.1 and later:

       smtpd_reject_unlisted_sender (no)
              Request  that  the Postfix SMTP server rejects mail from unknown
              sender addresses, even when no  explicit  reject_unlisted_sender
              access restriction is specified.

       smtpd_reject_unlisted_recipient (yes)
              Request  that  the  Postfix SMTP server rejects mail for unknown
              recipient     addresses,     even     when      no      explicit
              reject_unlisted_recipient access restriction is specified.

       Available in Postfix version 2.2 and later:

       smtpd_end_of_data_restrictions (empty)
              Optional  access  restrictions  that  the  Postfix  SMTP  server
              applies in the context of the SMTP END-OF-DATA command.

SENDER AND RECIPIENT ADDRESS VERIFICATION CONTROLS

       Postfix  version  2.1   introduces   sender   and   recipient   address
       verification.   This  feature  is  implemented  by  sending probe email
       messages that are not actually delivered.  This  feature  is  requested
       via the reject_unverified_sender and reject_unverified_recipient access
       restrictions.  The status of verification probes is maintained  by  the
       verify(8)   server.    See  the  file  ADDRESS_VERIFICATION_README  for
       information  about  how  to   configure   and   operate   the   Postfix
       sender/recipient address verification service.

       address_verify_poll_count (3)
              How many times to query the verify(8) service for the completion
              of an address verification request in progress.

       address_verify_poll_delay (3s)
              The delay between queries  for  the  completion  of  an  address
              verification request in progress.

       address_verify_sender (postmaster)
              The sender address to use in address verification probes.

       unverified_sender_reject_code (450)
              The numerical Postfix SMTP server response code when a recipient
              address is rejected by the reject_unverified_sender restriction.

       unverified_recipient_reject_code (450)
              The  numerical  Postfix  SMTP  server  response when a recipient
              address   is   rejected   by   the   reject_unverified_recipient
              restriction.

ACCESS CONTROL RESPONSES

       The following parameters control numerical SMTP reply codes and/or text
       responses.

       access_map_reject_code (554)
              The numerical Postfix SMTP server response code when a client is
              rejected by an access(5) map restriction.

       defer_code (450)
              The  numerical  Postfix  SMTP server response code when a remote
              SMTP client request is rejected by the "defer" restriction.

       invalid_hostname_reject_code (501)
              The numerical Postfix SMTP server response code when the  client
              HELO   or   EHLO   command   parameter   is   rejected   by  the
              reject_invalid_hostname restriction.

       maps_rbl_reject_code (554)
              The numerical Postfix SMTP server response code  when  a  remote
              SMTP   client  request  is  blocked  by  the  reject_rbl_client,
              reject_rhsbl_client,           reject_rhsbl_sender            or
              reject_rhsbl_recipient restriction.

       non_fqdn_reject_code (504)
              The  numerical  Postfix  SMTP  server  reply  code when a client
              request   is   rejected   by    the    reject_non_fqdn_hostname,
              reject_non_fqdn_sender or reject_non_fqdn_recipient restriction.

       reject_code (554)
              The numerical Postfix SMTP server response code  when  a  remote
              SMTP client request is rejected by the "reject" restriction.

       relay_domains_reject_code (554)
              The  numerical  Postfix  SMTP server response code when a client
              request is rejected by the  reject_unauth_destination  recipient
              restriction.

       unknown_address_reject_code (450)
              The numerical Postfix SMTP server response code when a sender or
              recipient      address      is       rejected       by       the
              reject_unknown_sender_domain  or reject_unknown_recipient_domain
              restriction.

       unknown_client_reject_code (450)
              The numerical Postfix SMTP server response code  when  a  client
              without  valid  address  <=>  name  mapping  is  rejected by the
              reject_unknown_client restriction.

       unknown_hostname_reject_code (450)
              The  numerical  Postfix  SMTP  server  response  code  when  the
              hostname  specified with the HELO or EHLO command is rejected by
              the reject_unknown_hostname restriction.

       Available in Postfix version 2.0 and later:

       default_rbl_reply (see β€β€™postconf -dβ€β€™ output)
              The default SMTP server response template for a request that  is
              rejected by an RBL-based restriction.

       multi_recipient_bounce_reject_code (550)
              The  numerical  Postfix  SMTP server response code when a remote
              SMTP     client     request     is      blocked      by      the
              reject_multi_recipient_bounce restriction.

       rbl_reply_maps (empty)
              Optional lookup tables with RBL response templates.

MISCELLANEOUS CONTROLS

       config_directory (see β€β€™postconf -dβ€β€™ output)
              The  default  location  of  the  Postfix  main.cf  and master.cf
              configuration files.

       daemon_timeout (18000s)
              How much time a Postfix daemon process  may  take  to  handle  a
              request before it is terminated by a built-in watchdog timer.

       command_directory (see β€β€™postconf -dβ€β€™ output)
              The location of all postfix administrative commands.

       double_bounce_sender (double-bounce)
              The   sender   address  of  postmaster  notifications  that  are
              generated by the mail system.

       ipc_timeout (3600s)
              The time limit for sending  or  receiving  information  over  an
              internal communication channel.

       mail_name (Postfix)
              The  mail system name that is displayed in Received: headers, in
              the SMTP greeting banner, and in bounced mail.

       mail_owner (postfix)
              The UNIX system account that owns the  Postfix  queue  and  most
              Postfix daemon processes.

       max_idle (100s)
              The  maximum  amount of time that an idle Postfix daemon process
              waits for the next service request before exiting.

       max_use (100)
              The maximal number  of  connection  requests  before  a  Postfix
              daemon process terminates.

       myhostname (see β€β€™postconf -dβ€β€™ output)
              The internet hostname of this mail system.

       mynetworks (see β€β€™postconf -dβ€β€™ output)
              The  list  of  "trusted"  SMTP clients that have more privileges
              than "strangers".

       myorigin ($myhostname)
              The domain name that locally-posted mail appears to  come  from,
              and that locally posted mail is delivered to.

       process_id (read-only)
              The process ID of a Postfix command or daemon process.

       process_name (read-only)
              The process name of a Postfix command or daemon process.

       queue_directory (see β€β€™postconf -dβ€β€™ output)
              The location of the Postfix top-level queue directory.

       recipient_delimiter (empty)
              The   separator   between  user  names  and  address  extensions
              (user+foo).

       smtpd_banner ($myhostname ESMTP $mail_name)
              The text that follows the 220 status code in the  SMTP  greeting
              banner.

       syslog_facility (mail)
              The syslog facility of Postfix logging.

       syslog_name (postfix)
              The  mail  system  name that is prepended to the process name in
              syslog  records,  so  that   "smtpd"   becomes,   for   example,
              "postfix/smtpd".

       Available in Postfix version 2.2 and later:

       smtpd_forbidden_commands (CONNECT, GET, POST)
              List  of  commands  that  causes  the  Postfix  SMTP  server  to
              immediately terminate the session with a 221 code.

SEE ALSO

       anvil(8), connection/rate limiting
       cleanup(8), message canonicalization
       tlsmgr(8), TLS session and PRNG management
       trivial-rewrite(8), address resolver
       verify(8), address verification service
       postconf(5), configuration parameters
       master(5), generic daemon options
       master(8), process manager
       syslogd(8), system logging

README FILES

       Use "postconf readme_directory" or "postconf html_directory" to  locate
       this information.
       ADDRESS_CLASS_README, blocking unknown hosted or relay recipients
       ADDRESS_REWRITING_README Postfix address manipulation
       FILTER_README, external after-queue content filter
       LOCAL_RECIPIENT_README, blocking unknown local recipients
       SMTPD_ACCESS_README, built-in access policies
       SMTPD_POLICY_README, external policy server
       SMTPD_PROXY_README, external before-queue content filter
       SASL_README, Postfix SASL howto
       TLS_README, Postfix STARTTLS howto
       VERP_README, Postfix XVERP extension
       XCLIENT_README, Postfix XCLIENT extension
       XFORWARD_README, Postfix XFORWARD extension

LICENSE

       The Secure Mailer license must be distributed with this software.

AUTHOR(S)

       Wietse Venema
       IBM T.J. Watson Research
       P.O. Box 704
       Yorktown Heights, NY 10598, USA

       TLS support originally by:
       Lutz Jaenicke
       BTU Cottbus
       Allgemeine Elektrotechnik
       Universitaetsplatz 3-4
       D-03044 Cottbus, Germany

                                                                      SMTPD(8)