Priority:
Determine timeouts in the queue sendmail
Mail messages can be placed into the queue either intentionally or because they could not be delivered immediately. Once they are in the queue, two time periods come into play. First is the period of time that the message should remain in the queue before a warning is issued to the sender. Second is the total period of time that the message should remain in the queue before it is bounced as a failed message.
Beginning with V8.7 sendmail, it
is possible to tailor these intervals on the basis
of three distinct priorities of mail. The new
Priority:
header tells sendmail which
priority a message possesses:
Priority: pri
Here, pri
can have one of
three possible values: urgent
, normal
, and non-urgent
. These values correspond
directly to the priorities specified by the Timeout.queuewarn
option
(Timeout.queuewarn (V8.7 and later) on page 1107) and Timeout.queuereturn
option (Timeout.queuereturn (V8.7 and later) on page 1106):
O Timeout.queuereturn.urgent=1d O Timeout.queuereturn.normal=2d O Timeout.queuereturn.non-urgent=4d
Here, a Priority:
header of normal
will cause the message containing it to bounce after
it has remained in the queue for two days.
The Priority:
header should never be declared in the configuration
file.
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