TRIVIAL-REWRITE(8)TRIVIAL-REWRITE(8)NAMEtrivial-rewrite - Postfix address rewriting and resolving daemon
SYNOPSIStrivial-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_re‐
write_domain to incomplete addresses. Otherwise the
result is identical to that of the local address rewrit‐
ing 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 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 $max_idle seconds of idle
time.
STANDARDS
None. The command does not interact with the outside world.
SECURITY
The trivial-rewrite(8) daemon is not security sensitive. By default,
this daemon does not talk to remote or local users. It can run at a
fixed low privilege in a chrooted environment.
DIAGNOSTICS
Problems and transactions are logged to syslogd(8).
CONFIGURATION PARAMETERS
On busy mail systems a long time may pass before a main.cf change
affecting trivial-rewrite(8) is picked up. Use the command "postfix
reload" to speed up a change.
The text below provides only a parameter summary. See postconf(5) for
more details including examples.
COMPATIBILITY CONTROLS
resolve_dequoted_address (yes)
Resolve a recipient address safely instead of correctly, by
looking inside quotes.
resolve_null_domain (no)
Resolve an address that ends in the "@" null domain as if the
local hostname were specified, instead of rejecting the address
as invalid.
resolve_numeric_domain (no)
Resolve "user@ipaddress" as "user@[ipaddress]", instead of
rejecting the address as invalid.
ADDRESS REWRITING CONTROLS
myorigin ($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 "@$myorigin" to
mail addresses without domain information.
append_dot_mydomain (yes)
With locally submitted mail, append the string ".$mydomain" to
addresses that have no ".domain" information.
recipient_delimiter (empty)
The separator between user names and address extensions
(user+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_mail‐
box_domains, or $relay_domains.
parent_domain_matches_subdomains (see 'postconf -d' output)
What Postfix features match subdomains of "domain.tld" automati‐
cally, instead of requiring an explicit ".domain.tld" pattern.
relayhost (empty)
The next-hop destination of non-local mail; overrides non-local
domains in recipient addresses.
transport_maps (empty)
Optional lookup tables with mappings from recipient address to
(message delivery transport, next-hop destination).
Available in Postfix version 2.3 and later:
sender_dependent_relayhost_maps (empty)
A sender-dependent override for the global relayhost parameter
setting.
ADDRESS VERIFICATION CONTROLS
Postfix version 2.1 introduces sender and recipient address verifica‐
tion. This feature is implemented by sending probe email messages that
are not actually delivered. By default, address verification probes
use the same route as regular mail. To override specific aspects of
message routing for address verification probes, specify one or more of
the following:
address_verify_local_transport ($local_transport)
Overrides the local_transport parameter setting for address ver‐
ification 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 ver‐
ification 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 (empty)
Overrides the sender_dependent_relayhost_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 con‐
figuration 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 the next service request before exiting.
max_use (100)
The maximal number of connection requests before a Postfix dae‐
mon process terminates.
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 (postfix)
The mail system name that is prepended to the process name in
syslog records, so that "smtpd" becomes, for example, "post‐
fix/smtpd".
Available in Postfix version 2.0 and later:
helpful_warnings (yes)
Log warnings about problematic configuration settings, and pro‐
vide helpful suggestions.
SEE ALSOpostconf(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
TRIVIAL-REWRITE(8)
