Sendmail Installation and Operation Guide
SMM:08-29
fileopen
The timeout for opening .forward and :include: files [60s, none].
control
The timeout for a complete control socket transaction to complete [2m, none].
hoststatus
How long status information about a host (e.g., host down) will be cached
before it is considered stale [30m, unspecified].
resolver.retrans The resolver's retransmission time interval (in seconds) [varies]. Sets both
Timeout.resolver.retrans.first and Timeout.resolver.retrans.normal.
resolver.retrans.first
The resolver's retransmission time interval (in seconds) for the first attempt to
deliver a message [varies].
resolver.retrans.normal
The resolver's retransmission time interval (in seconds) for all resolver
lookups except the first delivery attempt [varies].
resolver.retry The number of times to retransmit a resolver query. Sets both Time-
out.resolver.retry.first and Timeout.resolver.retry.normal [varies].
resolver.retry.first
The number of times to retransmit a resolver query for the first attempt to
deliver a message [varies].
resolver.retry.normal
The number of times to retransmit a resolver query for all resolver lookups
except the first delivery attempt [varies].
For compatibility with old configuration files, if no suboption is specified, all the timeouts
marked with a dagger () are set to the indicated value. All but those marked with a double dag-
ger () apply to client SMTP.
For example, the lines:
O Timeout.command=25m
O Timeout.datablock=3h
sets the server SMTP command timeout to 25 minutes and the input data block timeout to three
hours.
4.1.3. Message timeouts
After sitting in the queue for a few days, an undeliverable message will time out. This is
to insure that at least the sender is aware of the inability to send a message. The timeout is typi-
cally set to five days. It is sometimes considered convenient to also send a warning message if
the message is in the queue longer than a few hours (assuming you normally have good connec-
tivity; if your messages normally took several hours to send you wouldn't want to do this
because it wouldn't be an unusual event). These timeouts are set using the Timeout.queuere-
turn
and Timeout.queuewarn options in the configuration file (previously both were set using
the T option).
If the message is submitted using the
NOTIFY SMTP
extension, warning messages will
only be sent if
NOTIFY=DELAY
is specified. The queuereturn and queuewarn timeouts can be
further qualified with a tag based on the Precedence: field in the message; they must be one of
"urgent" (indicating a positive non-zero precedence), "normal" (indicating a zero precedence),
or "non-urgent" (indicating negative precedences). For example, setting "Timeout.queue-
warn.urgent=1h" sets the warning timeout for urgent messages only to one hour. The default if
no precedence is indicated is to set the timeout for all precedences. If the message has a normal
(default) precedence and it is a delivery status notification (DSN), Timeout.queuereturn.dsn
and Timeout.queuewarn.dsn can be used to give an alternative warn and return time for DSNs.
The value "now" can be used for -O Timeout.queuereturn to return entries immediately during a