# RETRY CONFIGURATION #
######################################################################
-# This single retry rule applies to all domains and all errors. It specifies
-# retries every 15 minutes for 2 hours, then increasing retry intervals,
-# starting at 2 hours and increasing each time by a factor of 1.5, up to 16
-# hours, then retries every 8 hours until 4 days have passed since the first
-# failed delivery.
-
# Domain Error Retries
# ------ ----- -------
-
begin retry
+## Note that retry rules specify when an address / host / mail should
+## become eligible for retrying. They do not specify when the retry
+## attempt will actually occur, as this is dependent on queue run
+## frequency and timing.
+
+# For mail to debian.org addresses, this rule starts with
+# retries every 10 minutes for 2 hours, then increasing retry intervals,
+# starting at 2 hours and increasing each time by a factor of 1.5, up to 16
+# hours, then retries every 8 hours until 14 days have passed since the first
+# failed delivery.
debian.org * F,2h,10m; G,16h,2h,1.5; F,14d,8h
+
+# Bounces should get retried every 10 minutes for up to 2 hours
* * senders=: F,2h,10m
+
+# Temporary errors at RCPT TO get retried at 5 minute intervals for
+# 2 hours, then 10 minute intervals for 4 hours, and finally at 15
+# minute intervals for 4 days. This assumes that the cause of the
+# error will get resolved quickly in most cases.
* rcpt_4xx F,2h,5m; F,4h,10m; F,4d,15m
+
+# For all remaining mails, addresses and hosts, this rule starts with
+# retries every 15 minutes for 2 hours, then increasing retry intervals,
+# starting at 2 hours and increasing each time by a factor of 1.5, up to 16
+# hours, then retries every 8 hours until 4 days have passed since the first
+# failed delivery.
* * F,2h,15m; G,16h,2h,1.5; F,4d,8h
# End of Exim 4 configuration