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
$mydomain to incomplete addresses; do swap_bangpath and
allow_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
$remote_header_rewrite_domain to incomplete addresses. Otherwise
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
information.
- recipient
- The envelope recipient address that is passed on to
nexthop.
- 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 master
server. Each server can handle multiple simultaneous connections. 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
$max_idle seconds of idle time.
STANDARDS
None. The command does not interact with the outside world.
SECURITY
The
trivial-rewrite(8) daemon is not security sensitive. By default, this
daemon does not talk to remote or local users. It can run at a fixed low
privilege in a chrooted environment.
DIAGNOSTICS
Problems and transactions are logged to
syslogd(8).
CONFIGURATION PARAMETERS
On busy mail systems a long time may pass before a
main.cf change
affecting
trivial-rewrite(8) is picked up. Use the command "
postfix reload" to speed up a change.
The text below provides only a parameter summary. See
postconf(5) for
more details including examples.
COMPATIBILITY CONTROLS
- resolve_dequoted_address (yes)
- Resolve a recipient address safely instead of correctly, by
looking inside quotes.
Available with Postfix version 2.1 and later:
- resolve_null_domain (no)
- Resolve an address that ends in the "@" null
domain as if the local hostname were specified, instead of rejecting the
address as invalid.
Available with Postfix version 2.3 and later:
- resolve_numeric_domain (no)
- Resolve "user@ipaddress" as
"user@[ipaddress]", instead of rejecting the address as
invalid.
Available with Postfix version 2.5 and later:
- allow_min_user (no)
- Allow a sender or recipient address to have `-' as the
first character.
ADDRESS REWRITING CONTROLS
- myorigin ($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 a user name from
its extension (example: user+foo), or a .forward file name from its
extension (example: .forward+foo).
- swap_bangpath (yes)
- Enable the rewriting of "site!user" into
"user@site".
Available in Postfix 2.2 and later:
- remote_header_rewrite_domain (empty)
- Don't rewrite message headers from remote clients at all
when this parameter is empty; otherwise, rewrite message headers and
append the specified domain name to incomplete addresses.
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 remote delivery to domains listed with
$relay_domains.
- default_transport (smtp)
- The default mail delivery transport and next-hop
destination for destinations that do not match $mydestination,
$inet_interfaces, $proxy_interfaces, $virtual_alias_domains,
$virtual_mailbox_domains, or $relay_domains.
- parent_domain_matches_subdomains (see 'postconf -d'
output)
- A list of Postfix features where the pattern
"example.com" also matches subdomains of example.com, instead of
requiring an explicit ".example.com" pattern.
- relayhost (empty)
- The next-hop destination of non-local mail; overrides
non-local domains in recipient addresses.
- transport_maps (empty)
- Optional lookup tables with mappings from recipient address
to (message delivery transport, next-hop destination).
Available in Postfix version 2.3 and later:
- sender_dependent_relayhost_maps (empty)
- A sender-dependent override for the global relayhost
parameter setting.
Available in Postfix version 2.5 and later:
- empty_address_relayhost_maps_lookup_key
(<>)
- The sender_dependent_relayhost_maps search string that will
be used instead of the null sender address.
Available in Postfix version 2.7 and later:
- empty_address_default_transport_maps_lookup_key
(<>)
- The sender_dependent_default_transport_maps search string
that will be used instead of the null sender address.
- sender_dependent_default_transport_maps (empty)
- A sender-dependent override for the global
default_transport parameter setting.
ADDRESS VERIFICATION CONTROLS
Postfix version 2.1 introduces sender and recipient address verification. This
feature is implemented by sending probe email messages that are not actually
delivered. By default, address verification probes use the same route as
regular mail. To override specific aspects of message routing for address
verification probes, specify one or more of the following:
- address_verify_local_transport
($local_transport)
- Overrides the local_transport parameter setting for address
verification 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
verification 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
verification probes.
- address_verify_transport_maps ($transport_maps)
- Overrides the transport_maps parameter setting for address
verification probes.
Available in Postfix version 2.3 and later:
- address_verify_sender_dependent_relayhost_maps
($sender_dependent_relayhost_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_dependent_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
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.
- 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
internal 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" responses.
- syslog_facility (mail)
- The syslog facility of Postfix logging.
- syslog_name (see 'postconf -d' output)
- 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 2.0 and later:
- helpful_warnings (yes)
- Log warnings about problematic configuration settings, and
provide helpful suggestions.
SEE ALSO
postconf(5), configuration parameters
transport(5), transport table format
relocated(5), format of the "user has moved" table
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, 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