LMTP(8)                                                   LMTP(8)


NAME
       lmtp - Postfix local delivery via LMTP

SYNOPSIS
       lmtp [generic Postfix daemon options]

DESCRIPTION
       The  LMTP  client processes message delivery requests from
       the queue manager. Each request specifies a queue file,  a
       sender address, a domain or host to deliver to, and recip-
       ient information.  This program expects to be run from the
       master(8) process manager.

       The  LMTP  client updates the queue file and marks recipi-
       ents as finished, or it informs  the  queue  manager  that
       delivery  should  be tried again at a later time. Delivery
       problem reports are sent to the bounce(8) or defer(8) dae-
       mon as appropriate.

       The  LMTP  client connects to the destination specified in
       the message delivery  request.  The  destination,  usually
       specified in the Postfix transport(5) table, has the form:

       unix:pathname
              Connect to the UNIX-domain server that is bound  to
              the   specified   pathname.  If  the  process  runs
              chrooted, an absolute pathname is interpreted rela-
              tive to the changed root directory.

       inet:host, inet:host:port (symbolic host)

       inet:[addr], inet:[addr]:port (numeric host)
              Connect to the specified IPV4 TCP port on the spec-
              ified host. If no port is specified, connect to the
              port  defined  as  lmtp in services(4).  If no such
              service is found, the  lmtp_tcp_port  configuration
              parameter (default value of 24) will be used.

              The   LMTP   client   does  not  perform  MX  (mail
              exchanger) lookups since those are defined only for
              mail delivery via SMTP.

       If  neither  unix:  nor  inet:  are  specified,  inet:  is
       assumed.

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

STANDARDS
       RFC 821 (SMTP protocol)
       RFC 1651 (SMTP service extensions)
       RFC 1870 (Message Size Declaration)



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LMTP(8)                                                   LMTP(8)


       RFC 2033 (LMTP protocol)
       RFC 2197 (Pipelining)

DIAGNOSTICS
       Problems and transactions are logged to syslogd(8).   Cor-
       rupted  message files are marked so that the queue manager
       can move them to the corrupt queue for further inspection.

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

BUGS
CONFIGURATION PARAMETERS
       The  following  main.cf parameters are especially relevant
       to this program. See the Postfix main.cf file  for  syntax
       details  and  for  default  values. Use the postfix reload
       command after a configuration change.

Miscellaneous
       debug_peer_level
              Verbose logging  level  increment  for  hosts  that
              match a pattern in the debug_peer_list parameter.

       debug_peer_list
              List  of  domain or network patterns. When a remote
              host matches a pattern, increase the  verbose  log-
              ging   level   by   the  amount  specified  in  the
              debug_peer_level parameter.

       error_notice_recipient
              Recipient   of    protocol/policy/resource/software
              error notices.

       notify_classes
              When  this  parameter  includes the protocol class,
              send mail to the  postmaster  with  transcripts  of
              LMTP sessions with protocol errors.

       lmtp_skip_quit_response
              Do  not  wait for the server response after sending
              QUIT.

       lmtp_tcp_port
              The TCP port to be used when connecting to  a  LMTP
              server.   Used as backup if the lmtp service is not
              found in services(4).

Resource controls
       lmtp_cache_connection
              Should we cache the connection to the LMTP  server?
              The  effectiveness  of  cached  connections will be
              determined by the number of LMTP  servers  in  use,
              and  the  concurrency  limit specified for the LMTP



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LMTP(8)                                                   LMTP(8)


              client.  Cached connections are closed under any of
              the following conditions:

              o      The  LMTP client idle time limit is reached.
                     This limit is  specified  with  the  Postfix
                     max_idle configuration parameter.

              o      A  delivery  request  specifies  a different
                     destination than the one currently cached.

              o      The  per-process  limit  on  the  number  of
                     delivery requests is reached.  This limit is
                     specified with the Postfix max_use  configu-
                     ration parameter.

              o      Upon  the onset of another delivery request,
                     the LMTP server associated with the  current
                     session  does  not  respond to the RSET com-
                     mand.

       transport_destination_concurrency_limit
              Limit the number of parallel deliveries to the same
              destination   via  this  mail  delivery  transport.
              transport is the name of the service  as  specified
              in  the master.cf file.  The default limit is taken
              from   the    default_destination_concurrency_limit
              parameter.

       transport_destination_recipient_limit
              Limit the number of recipients per message delivery
              via this mail delivery transport. transport is  the
              name  of  the service as specified in the master.cf
              file.   The  default  limit  is  taken   from   the
              default_destination_recipient_limit parameter.

              This  parameter  becomes  significant  if  the LMTP
              client is  used  for  local  delivery.   Some  LMTP
              servers  can  optimize delivery of the same message
              to multiple recipients. The default limit for local
              mail delivery is 1.

              Setting  this  parameter  to  0  will  lead  to  an
              unbounded number of recipients per delivery.   How-
              ever,  this  could  be  risky since it may make the
              machine vulnerable to running out of  resources  if
              messages  are encountered with an inordinate number
              of recipients.  Exercise  care  when  setting  this
              parameter.

Timeout controls
       lmtp_connect_timeout
              Timeout  in seconds for opening a connection to the
              LMTP server.  If no connection can be  made  within
              the deadline, the message is deferred.



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LMTP(8)                                                   LMTP(8)


       lmtp_lhlo_timeout
              Timeout  in  seconds  for sending the LHLO command,
              and for receiving the server response.

       lmtp_mail_timeout
              Timeout in seconds for sending the MAIL  FROM  com-
              mand, and for receiving the server response.

       lmtp_rcpt_timeout
              Timeout in seconds for sending the RCPT TO command,
              and for receiving the server response.

       lmtp_data_init_timeout
              Timeout in seconds for sending  the  DATA  command,
              and for receiving the server response.

       lmtp_data_xfer_timeout
              Timeout in seconds for sending the message content.

       lmtp_data_done_timeout
              Timeout in seconds for sending the "." command, and
              for receiving the server response. When no response
              is received, a warning is logged that the mail  may
              be delivered multiple times.

       lmtp_rset_timeout
              Timeout  in  seconds  for sending the RSET command,
              and for receiving the server response.

       lmtp_quit_timeout
              Timeout in seconds for sending  the  QUIT  command,
              and for receiving the server response.

SEE ALSO
       bounce(8) non-delivery status reports
       local(8) local mail delivery
       master(8) process manager
       qmgr(8) queue manager
       services(4) Internet services and aliases
       spawn(8) auxiliary command spawner
       syslogd(8) system logging

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

       Alterations for LMTP by:
       Philip A. Prindeville



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LMTP(8)                                                   LMTP(8)


       Mirapoint, Inc.
       USA.

       Additional work on LMTP by:
       Amos Gouaux
       University of Texas at Dallas
       P.O. Box 830688, MC34
       Richardson, TX 75083, USA

















































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