On Tue, Mar 07, 2017 at 10:28:59AM +0100, Peter Rindfuss wrote:
> We are using Exim 4.88 on Debian with a non-Debian config. We deliver to
> our mailboxes on a separate Dovecot IMAP machine using LMTP over TCP
> (SMTP transport). A few times a day we see "Connection timed out" on the
> transport. It strikes me as odd that the time between the reception of a
> message and the delivery timeout is typically around 20 seconds, whereas
> all timeout values are at their defaults, which is 5 minutes for
> connect, command and data. Any ideas on this?
Chapter 30.4 says:
connect_timeout Use: smtp Type: time Default: 5m
This sets a timeout for the connect() function, which sets up a
TCP/IP call to a remote host. A setting of zero allows the system
timeout (typically several minutes) to act. To have any effect, the
value of this option must be less than the system timeout. However,
it has been observed that on some systems there is no system
timeout, which is why the default value for this option is 5
minutes, a value recommended by RFC 1123.
Check the system (kernel) connect timeout value.
--
Eugene Berdnikov
