> On May 2, 2016, at 10:40 PM, Noel Jones <njo...@megan.vbhcs.org> wrote: > > On 5/2/2016 8:42 PM, Steven Peterson wrote: >> Thank you! This was very helpful. >> >> By setting minimal_backoff_time to 300s globally, postfix now >> attempts to send deferred messages to comcast.net >> <http://comcast.net> every 10 minutes. This is an improvement, but >> it is not obvious why it sends every 10 minutes (600s) and not every >> 5 minutes (300 seconds). Is there another setting that is >> preventing it from repeating every 300 seconds as the >> minimal_backoff_time setting indicates? >> >> Best, Steve >> > > > First, note the minimal backoff is a guaranteed minimum, not a timer > after which an attempt will be tried immediately. Other mail in the > queue or system load may delay the next retry. A badly clogged mail > queue may take hours until it gets around to a retry. > > The queue delay settings are documented here: > http://www.postfix.org/TUNING_README.html#hammer
Also in play is the value of queue_run_delay which is "The time between deferred queue scans by the queue manager”. The default is 300s so with minimal_backoff_time also 300s, when a send attempt ends and then 300s (minimal_backoff_time) elapses, the queue run has just occurred and so it waits another almost 300s until the next queue run. If you want it to try every 300s, set minimal_backoff_time to less than queue_run_delay so that the next queue run occurs soon after the backoff_time expires. Note also that the time between runs increases until it reaches maximal_backoff_time. Read the documentation Noel referenced above. -- Larry Stone lston...@stonejongleux.com
