TRIVIAL-REWRITE(8) System Manager's Manual TRIVIAL-REWRITE(8)
NAME
trivial-rewrite - Postfix address rewriting and resolving daemon
SYNOPSIS
trivial-rewrite [generic Postfix daemon options]
DESCRIPTION
The trivial-rewrite(8) daemon processes three types of client service
requests:
rewrite context address
Rewrite an address to standard form, according to the address
rewriting context:
local Append the domain names specified with $myorigin or $mydo-
main to incomplete addresses; do swap_bangpath and al-
low_percent_hack processing as described below, and strip
source routed addresses (@site,@site:user@domain) to
user@domain form.
remote Append the domain name specified with $re-
mote_header_rewrite_domain to incomplete addresses. Other-
wise the result is identical to that of the local address
rewriting context. This prevents Postfix from appending
the local domain to spam from poorly written remote
clients.
resolve sender address
Resolve the address to a (transport, nexthop, recipient, flags)
quadruple. The meaning of the results is as follows:
transport
The delivery agent to use. This is the first field of an
entry in the master.cf file.
nexthop
The host to send to and optional delivery method informa-
tion.
recipient
The envelope recipient address that is passed on to nex-
thop.
flags The address class, whether the address requires relaying,
whether the address has problems, and whether the request
failed.
verify sender address
Resolve the address for address verification purposes.
SERVER PROCESS MANAGEMENT
The trivial-rewrite(8) servers run under control by the Postfix mas-
ter(8) server. Each server can handle multiple simultaneous connec-
tions. When all servers are busy while a client connects, the master
creates a new server process, provided that the trivial-rewrite server
process limit is not exceeded. Each trivial-rewrite server terminates
after serving at least $max_use clients of after $max_idle seconds of
idle time.
STANDARDS
None. The command does not interact with the outside world.
SECURITY
The trivial-rewrite(8) daemon is not security sensitive. By default,
this daemon does not talk to remote or local users. It can run at a
fixed low privilege in a chrooted environment.
DIAGNOSTICS
Problems and transactions are logged to syslogd(8) or postlogd(8).
CONFIGURATION PARAMETERS
On busy mail systems a long time may pass before a main.cf change af-
fecting trivial-rewrite(8) is picked up. Use the command "postfix re-
load" to speed up a change.
The text below provides only a parameter summary. See postconf(5) for
more details including examples.
COMPATIBILITY CONTROLS
resolve_dequoted_address (yes)
Resolve a recipient address safely instead of correctly, by look-
ing inside quotes.
Available with Postfix version 2.1 and later:
resolve_null_domain (no)
Resolve an address that ends in the "@" null domain as if the lo-
cal hostname were specified, instead of rejecting the address as
invalid.
Available with Postfix version 2.3 and later:
resolve_numeric_domain (no)
Resolve "user@ipaddress" as "user@[ipaddress]", instead of re-
jecting the address as invalid.
Available with Postfix version 2.5 and later:
allow_min_user (no)
Allow a sender or recipient address to have `-' as the first
character.
ADDRESS REWRITING CONTROLS
myorigin ($myhostname)
The domain name that locally-posted mail appears to come from,
and that locally posted mail is delivered to.
allow_percent_hack (yes)
Enable the rewriting of the form "user%domain" to "user@domain".
append_at_myorigin (yes)
With locally submitted mail, append the string "@$myorigin" to
mail addresses without domain information.
append_dot_mydomain (Postfix >= 3.0: no, Postfix < 3.0: yes)
With locally submitted mail, append the string ".$mydomain" to
addresses that have no ".domain" information.
recipient_delimiter (empty)
The set of characters that can separate an email address local-
part, user name, or a .forward file name from its extension.
swap_bangpath (yes)
Enable the rewriting of "site!user" into "user@site".
Available in Postfix 2.2 and later:
remote_header_rewrite_domain (empty)
Rewrite or add message headers in mail from remote clients if the
remote_header_rewrite_domain parameter value is non-empty, updat-
ing incomplete addresses with the domain specified in the re-
mote_header_rewrite_domain parameter, and adding missing headers.
ROUTING CONTROLS
The following is applicable to Postfix version 2.0 and later. Earlier
versions do not have support for: virtual_transport, relay_transport,
virtual_alias_domains, virtual_mailbox_domains or proxy_interfaces.
local_transport (local:$myhostname)
The default mail delivery transport and next-hop destination for
final delivery to domains listed with mydestination, and for
[ipaddress] destinations that match $inet_interfaces or
$proxy_interfaces.
virtual_transport (virtual)
The default mail delivery transport and next-hop destination for
final delivery to domains listed with $virtual_mailbox_domains.
relay_transport (relay)
The default mail delivery transport and next-hop destination for
the relay domain address class: recipient domains that match $re-
lay_domains.
default_transport (smtp)
The default mail delivery transport and next-hop destination for
the default domain class: recipient domains that do not match
$mydestination, $inet_interfaces, $proxy_interfaces, $vir-
tual_alias_domains, $virtual_mailbox_domains, or $relay_domains.
parent_domain_matches_subdomains (see 'postconf -d' output)
A list of Postfix features where the pattern "example.com" also
matches subdomains of example.com, instead of requiring an ex-
plicit ".example.com" pattern.
relayhost (empty)
The next-hop destination(s) for non-local mail; takes precedence
over non-local domains in recipient addresses.
transport_maps (empty)
Optional lookup tables with mappings from recipient address to
(message delivery transport, next-hop destination).
Available in Postfix version 2.3 and later:
sender_dependent_relayhost_maps (empty)
A sender-dependent override for the global relayhost parameter
setting.
Available in Postfix version 2.5 and later:
empty_address_relayhost_maps_lookup_key (<>)
The sender_dependent_relayhost_maps search string that will be
used instead of the null sender address.
Available in Postfix version 2.7 and later:
empty_address_default_transport_maps_lookup_key (<>)
The sender_dependent_default_transport_maps search string that
will be used instead of the null sender address.
sender_dependent_default_transport_maps (empty)
A sender-dependent override for the global default_transport pa-
rameter setting.
ADDRESS VERIFICATION CONTROLS
Postfix version 2.1 introduces sender and recipient address verifica-
tion. This feature is implemented by sending probe email messages that
are not actually delivered. By default, address verification probes use
the same route as regular mail. To override specific aspects of message
routing for address verification probes, specify one or more of the fol-
lowing:
address_verify_local_transport ($local_transport)
Overrides the local_transport parameter setting for address veri-
fication probes.
address_verify_virtual_transport ($virtual_transport)
Overrides the virtual_transport parameter setting for address
verification probes.
address_verify_relay_transport ($relay_transport)
Overrides the relay_transport parameter setting for address veri-
fication probes.
address_verify_default_transport ($default_transport)
Overrides the default_transport parameter setting for address
verification probes.
address_verify_relayhost ($relayhost)
Overrides the relayhost parameter setting for address verifica-
tion probes.
address_verify_transport_maps ($transport_maps)
Overrides the transport_maps parameter setting for address veri-
fication probes.
Available in Postfix version 2.3 and later:
address_verify_sender_dependent_relayhost_maps ($sender_dependent_relay-
host_maps)
Overrides the sender_dependent_relayhost_maps parameter setting
for address verification probes.
Available in Postfix version 2.7 and later:
address_verify_sender_dependent_default_transport_maps ($sender_depen-
dent_default_transport_maps)
Overrides the sender_dependent_default_transport_maps parameter
setting for address verification probes.
MISCELLANEOUS CONTROLS
config_directory (see 'postconf -d' output)
The default location of the Postfix main.cf and master.cf config-
uration files.
daemon_timeout (18000s)
How much time a Postfix daemon process may take to handle a re-
quest before it is terminated by a built-in watchdog timer.
empty_address_recipient (MAILER-DAEMON)
The recipient of mail addressed to the null address.
ipc_timeout (3600s)
The time limit for sending or receiving information over an in-
ternal communication channel.
max_idle (100s)
The maximum amount of time that an idle Postfix daemon process
waits for an incoming connection before terminating voluntarily.
max_use (100)
The maximal number of incoming connections that a Postfix daemon
process will service before terminating voluntarily.
relocated_maps (empty)
Optional lookup tables with new contact information for users or
domains that no longer exist.
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 'postconf -d' output)
The location of the Postfix top-level queue directory.
show_user_unknown_table_name (yes)
Display the name of the recipient table in the "User unknown" re-
sponses.
syslog_facility (mail)
The syslog facility of Postfix logging.
syslog_name (see 'postconf -d' output)
A prefix that is prepended to the process name in syslog records,
so that, for example, "smtpd" becomes "prefix/smtpd".
Available in Postfix version 2.0 and later:
helpful_warnings (yes)
Log warnings about problematic configuration settings, and pro-
vide helpful suggestions.
Available in Postfix 3.3 and later:
service_name (read-only)
The master.cf service name of a Postfix daemon process.
SEE ALSO
postconf(5), configuration parameters
transport(5), transport table format
relocated(5), format of the "user has moved" table
master(8), process manager
postlogd(8), Postfix logging
syslogd(8), system logging
README FILES
Use "postconf readme_directory" or "postconf html_directory" to locate
this information.
ADDRESS_CLASS_README, Postfix address classes howto
ADDRESS_VERIFICATION_README, Postfix address verification
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
Wietse Venema
Google, Inc.
111 8th Avenue
New York, NY 10011, USA
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