NAME
oqmgr
-
old Postfix queue manager
SYNOPSIS
ooqqmmggrr [generic Postfix daemon options]
DESCRIPTION
The ooqqmmggrr(8) daemon awaits the arrival of incoming mail
and arranges for its delivery via Postfix delivery processes.
The actual mail routing strategy is delegated to the
ttrriivviiaall--rreewwrriittee(8) daemon.
This program expects to be run from the mmaasstteerr(8) process
manager.
Mail addressed to the local ddoouubbllee--bboouunnccee address is
logged and discarded. This stops potential loops caused by
undeliverable bounce notifications.
MAIL QUEUES
The ooqqmmggrr(8) daemon maintains the following queues:
-
iinnccoommiinngg
Inbound mail from the network, or mail picked up by the
-
local ppiicckkuupp(8) agent from the mmaaiillddrroopp directory.
-
aaccttiivvee
Messages that the queue manager has opened for delivery. Only
-
a limited number of messages is allowed to enter the aaccttiivvee
queue (leaky bucket strategy, for a fixed delivery rate).
-
ddeeffeerrrreedd
Mail that could not be delivered upon the first attempt. The queue
-
manager implements exponential backoff by doubling the time between
delivery attempts.
-
ccoorrrruupptt
Unreadable or damaged queue files are moved here for inspection.
-
-
hhoolldd
Messages that are kept "on hold" are kept here until someone
-
sets them free.
DELIVERY STATUS REPORTS
The ooqqmmggrr(8) daemon keeps an eye on per-message delivery status
reports in the following directories. Each status report file has
the same name as the corresponding message file:
-
bboouunnccee
Per-recipient status information about why mail is bounced.
-
These files are maintained by the bboouunnccee(8) daemon.
-
ddeeffeerr
Per-recipient status information about why mail is delayed.
-
These files are maintained by the ddeeffeerr(8) daemon.
-
ttrraaccee
Per-recipient status information as requested with the
-
Postfix "sseennddmmaaiill --vv" or "sseennddmmaaiill --bbvv" command.
These files are maintained by the ttrraaccee(8) daemon.
The ooqqmmggrr(8) daemon is responsible for asking the
bboouunnccee(8), ddeeffeerr(8) or ttrraaccee(8) daemons to
send delivery reports.
STRATEGIES
The queue manager implements a variety of strategies for
either opening queue files (input) or for message delivery (output).
-
lleeaakkyy bbuucckkeett
This strategy limits the number of messages in the aaccttiivvee queue
-
and prevents the queue manager from running out of memory under
heavy load.
-
ffaaiirrnneessss
When the aaccttiivvee queue has room, the queue manager takes one
-
message from the iinnccoommiinngg queue and one from the ddeeffeerrrreedd
queue. This prevents a large mail backlog from blocking the delivery
of new mail.
-
ssllooww ssttaarrtt
This strategy eliminates "thundering herd" problems by slowly
-
adjusting the number of parallel deliveries to the same destination.
-
rroouunndd rroobbiinn
The queue manager sorts delivery requests by destination.
-
Round-robin selection prevents one destination from dominating
deliveries to other destinations.
-
eexxppoonneennttiiaall bbaacckkooffff
Mail that cannot be delivered upon the first attempt is deferred.
-
The time interval between delivery attempts is doubled after each
attempt.
-
ddeessttiinnaattiioonn ssttaattuuss ccaacchhee
The queue manager avoids unnecessary delivery attempts by
-
maintaining a short-term, in-memory list of unreachable destinations.
TRIGGERS
On an idle system, the queue manager waits for the arrival of
trigger events, or it waits for a timer to go off. A trigger
is a one-byte message.
Depending on the message received, the queue manager performs
one of the following actions (the message is followed by the
symbolic constant used internally by the software):
-
DD ((QQMMGGRR__RREEQQ__SSCCAANN__DDEEFFEERRRREEDD))
Start a deferred queue scan. If a deferred queue scan is already
-
in progress, that scan will be restarted as soon as it finishes.
-
II ((QQMMGGRR__RREEQQ__SSCCAANN__IINNCCOOMMIINNGG))
Start an incoming queue scan. If an incoming queue scan is already
-
in progress, that scan will be restarted as soon as it finishes.
-
AA ((QQMMGGRR__RREEQQ__SSCCAANN__AALLLL))
Ignore deferred queue file time stamps. The request affects
-
the next deferred queue scan.
-
FF ((QQMMGGRR__RREEQQ__FFLLUUSSHH__DDEEAADD))
Purge all information about dead transports and destinations.
-
-
WW ((TTRRIIGGGGEERR__RREEQQ__WWAAKKEEUUPP))
Wakeup call, This is used by the master server to instantiate
-
servers that should not go away forever. The action is to start
an incoming queue scan.
The ooqqmmggrr(8) daemon reads an entire buffer worth of triggers.
Multiple identical trigger requests are collapsed into one, and
trigger requests are sorted so that AA and FF precede
DD and II. Thus, in order to force a deferred queue run,
one would request AA FF DD; in order to notify the queue manager
of the arrival of new mail one would request II.
STANDARDS
RFC 3463 (Enhanced status codes)
RFC 3464 (Delivery status notifications)
SECURITY
The ooqqmmggrr(8) daemon is not security sensitive. It reads
single-character messages from untrusted local users, and thus may
be susceptible to denial of service attacks. The ooqqmmggrr(8) daemon
does not talk to the outside world, and it can be run at fixed low
privilege in a chrooted environment.
DIAGNOSTICS
Problems and transactions are logged to the ssyysslloogg(8) daemon.
Corrupted message files are saved to the ccoorrrruupptt queue
for further inspection.
Depending on the setting of the nnoottiiffyy__ccllaasssseess parameter,
the postmaster is notified of bounces and of other trouble.
BUGS
A single queue manager process has to compete for disk access with
multiple front-end processes such as cclleeaannuupp(8). A sudden burst of
inbound mail can negatively impact outbound delivery rates.
CONFIGURATION PARAMETERS
Changes to mmaaiinn..ccff are not picked up automatically,
as ooqqmmggrr(8)
is a persistent process. Use the command "ppoossttffiixx rreellooaadd" after
a configuration change.
The text below provides only a parameter summary. See
ppoossttccoonnff(5) for more details including examples.
In the text below, _t_r_a_n_s_p_o_r_t is the first field in a
mmaasstteerr..ccff entry.
COMPATIBILITY CONTROLS
Available before Postfix version 2.5:
-
aallllooww__mmiinn__uusseerr ((nnoo))
Allow a sender or recipient address to have `-' as the first
-
character.
Available with Postfix version 2.7 and later:
-
ddeeffaauulltt__ffiilltteerr__nneexxtthhoopp ((eemmppttyy))
When a content_filter or FILTER request specifies no explicit
-
next-hop destination, use $default_filter_nexthop instead; when
that value is empty, use the domain in the recipient address.
ACTIVE QUEUE CONTROLS
-
qqmmggrr__cclloogg__wwaarrnn__ttiimmee ((330000ss))
The minimal delay between warnings that a specific destination is
-
clogging up the Postfix active queue.
-
qqmmggrr__mmeessssaaggee__aaccttiivvee__lliimmiitt ((2200000000))
The maximal number of messages in the active queue.
-
-
qqmmggrr__mmeessssaaggee__rreecciippiieenntt__lliimmiitt ((2200000000))
The maximal number of recipients held in memory by the Postfix
-
queue manager, and the maximal size of the size of the short-term,
in-memory "dead" destination status cache.
DELIVERY CONCURRENCY CONTROLS
-
qqmmggrr__ffuuddggee__ffaaccttoorr ((110000))
Obsolete feature: the percentage of delivery resources that a busy
-
mail system will use up for delivery of a large mailing list
message.
-
iinniittiiaall__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy ((55))
The initial per-destination concurrency level for parallel delivery
-
to the same destination.
-
ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__lliimmiitt ((2200))
The default maximal number of parallel deliveries to the same
-
destination.
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__lliimmiitt (($$ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__lliimmiitt))
Idem, for delivery via the named message _t_r_a_n_s_p_o_r_t.
-
Available in Postfix version 2.5 and later:
-
_t_r_a_n_s_p_o_r_t__iinniittiiaall__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy (($$iinniittiiaall__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy))
Initial concurrency for delivery via the named message
-
_t_r_a_n_s_p_o_r_t.
-
ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ffaaiilleedd__ccoohhoorrtt__lliimmiitt ((11))
How many pseudo-cohorts must suffer connection or handshake
-
failure before a specific destination is considered unavailable
(and further delivery is suspended).
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ffaaiilleedd__ccoohhoorrtt__lliimmiitt (($$ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ffaaiilleedd__ccoohhoorrtt__lliimmiitt))
Idem, for delivery via the named message _t_r_a_n_s_p_o_r_t.
-
-
ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__nneeggaattiivvee__ffeeeeddbbaacckk ((11))
The per-destination amount of delivery concurrency negative
-
feedback, after a delivery completes with a connection or handshake
failure.
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__nneeggaattiivvee__ffeeeeddbbaacckk (($$ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__nneeggaattiivvee__ffeeeeddbbaacckk))
Idem, for delivery via the named message _t_r_a_n_s_p_o_r_t.
-
-
ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ppoossiittiivvee__ffeeeeddbbaacckk ((11))
The per-destination amount of delivery concurrency positive
-
feedback, after a delivery completes without connection or handshake
failure.
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ppoossiittiivvee__ffeeeeddbbaacckk (($$ddeeffaauulltt__ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ppoossiittiivvee__ffeeeeddbbaacckk))
Idem, for delivery via the named message _t_r_a_n_s_p_o_r_t.
-
-
ddeessttiinnaattiioonn__ccoonnccuurrrreennccyy__ffeeeeddbbaacckk__ddeebbuugg ((nnoo))
Make the queue manager's feedback algorithm verbose for performance
-
analysis purposes.
RECIPIENT SCHEDULING CONTROLS
-
ddeeffaauulltt__ddeessttiinnaattiioonn__rreecciippiieenntt__lliimmiitt ((5500))
The default maximal number of recipients per message delivery.
-
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__rreecciippiieenntt__lliimmiitt
Idem, for delivery via the named message _t_r_a_n_s_p_o_r_t.
-
OTHER RESOURCE AND RATE CONTROLS
-
mmiinniimmaall__bbaacckkooffff__ttiimmee ((330000ss))
The minimal time between attempts to deliver a deferred message;
-
prior to Postfix 2.4 the default value was 1000s.
-
mmaaxxiimmaall__bbaacckkooffff__ttiimmee ((44000000ss))
The maximal time between attempts to deliver a deferred message.
-
-
mmaaxxiimmaall__qquueeuuee__lliiffeettiimmee ((55dd))
The maximal time a message is queued before it is sent back as
-
undeliverable.
-
qquueeuuee__rruunn__ddeellaayy ((330000ss))
The time between deferred queue scans by the queue manager;
-
prior to Postfix 2.4 the default value was 1000s.
-
ttrraannssppoorrtt__rreettrryy__ttiimmee ((6600ss))
The time between attempts by the Postfix queue manager to contact
-
a malfunctioning message delivery transport.
Available in Postfix version 2.1 and later:
-
bboouunnccee__qquueeuuee__lliiffeettiimmee ((55dd))
The maximal time a bounce message is queued before it is considered
-
undeliverable.
Available in Postfix version 2.5 and later:
-
ddeeffaauulltt__ddeessttiinnaattiioonn__rraattee__ddeellaayy ((00ss))
The default amount of delay that is inserted between individual
-
deliveries to the same destination; with per-destination recipient
limit > 1, a destination is a domain, otherwise it is a recipient.
-
_t_r_a_n_s_p_o_r_t__ddeessttiinnaattiioonn__rraattee__ddeellaayy $$ddeeffaauulltt__ddeessttiinnaattiioonn__rraattee__ddeellaayy</bb>>
IIddeemm,, ffoorr ddeelliivveerryy vviiaa tthhee nnaammeedd mmeessssaaggee _t_r_a_n_s_p_o_r_t.
-
MISCELLANEOUS CONTROLS
-
ccoonnffiigg__ddiirreeccttoorryy ((sseeee ''ppoossttccoonnff --dd'' oouuttppuutt))
The default location of the Postfix main.cf and master.cf
-
configuration files.
-
ddeeffeerr__ttrraannssppoorrttss ((eemmppttyy))
The names of message delivery transports that should not deliver mail
-
unless someone issues "sseennddmmaaiill --qq" or equivalent.
-
ddeellaayy__llooggggiinngg__rreessoolluuttiioonn__lliimmiitt ((22))
The maximal number of digits after the decimal point when logging
-
sub-second delay values.
-
hheellppffuull__wwaarrnniinnggss ((yyeess))
Log warnings about problematic configuration settings, and provide
-
helpful suggestions.
-
iippcc__ttiimmeeoouutt ((33660000ss))
The time limit for sending or receiving information over an internal
-
communication channel.
-
pprroocceessss__iidd ((rreeaadd--oonnllyy))
The process ID of a Postfix command or daemon process.
-
-
pprroocceessss__nnaammee ((rreeaadd--oonnllyy))
The process name of a Postfix command or daemon process.
-
-
qquueeuuee__ddiirreeccttoorryy ((sseeee ''ppoossttccoonnff --dd'' oouuttppuutt))
The location of the Postfix top-level queue directory.
-
-
ssyysslloogg__ffaacciilliittyy ((mmaaiill))
The syslog facility of Postfix logging.
-
-
ssyysslloogg__nnaammee ((sseeee ''ppoossttccoonnff --dd'' oouuttppuutt))
The mail system name that is prepended to the process name in syslog
-
records, so that "smtpd" becomes, for example, "postfix/smtpd".
FILES
/var/spool/postfix/incoming, incoming queue
/var/spool/postfix/active, active queue
/var/spool/postfix/deferred, deferred queue
/var/spool/postfix/bounce, non-delivery status
/var/spool/postfix/defer, non-delivery status
/var/spool/postfix/trace, delivery status
SEE ALSO
trivial-rewrite(8), address routing
bounce(8), delivery status reports
postconf(5), configuration parameters
master(5), generic daemon options
master(8), process manager
syslogd(8), system logging
README FILES
Use "ppoossttccoonnff rreeaaddmmee__ddiirreeccttoorryy" or
"ppoossttccoonnff hhttmmll__ddiirreeccttoorryy" to locate this information.
QSHAPE_README, Postfix queue analysis
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