sendmail, 4th Edition

QueueTimeout

Limit life of a message in the queue Deprecated

When mail cannot be delivered promptly, it is left in the queue. At intervals specified by sendmail’s -q command-line switch, or by a queue group’s Interval= setting, periodic re-delivery of that queued mail is attempted. The maximum total time a mail message can remain in the queue before being bounced as undeliverable is defined by this QueueTimeout option. (Note that the QueueTimeout option has been deprecated in favor of the Timeout option of V8.7 sendmail.)

The forms of the QueueTimeout option are as follows:

O QueueTimeout=qtime                    ← configuration file (deprecated)
-OQueueTimeout=qtime                    ← command line (deprecated)
define(`confMESSAGE_TIMEOUT',`qtime')   ← mc configuration (deprecated)
OTqtime                                 ← configuration file (deprecated)
-oTqtime                                ← command line (deprecated)

The argument qtime is of type time. If this argument is missing or if the entire QueueTimeout option is missing, the value given to qtime is zero, and no mail is ever queued.^[412] The qtime is generally specified as a number of days—5d, for example. (Incidentally, RFC1123 recommends five days as a minimum.)

All queued mail is timed out on the basis of its creation time compared to the timeout period specified by the QueueTimeout option. Each queued message has its creation time stored in its qf file’s T line (T line on page 456). When sendmail is run (either as a daemon or by hand) to process the queue, it gets its timeout period from the value of the QueueTimeout