Dear folks,
we sent all outgoing emails through a bunch of servers which do the
filtering, and this works beautifully in general.
However, it leaves some mails waiting in the queue unnessarily long if
one of the MX-ed servers is taken down. I've tried to mangled some
parameters, but haven't gotten the desired behaviour. Insights much
appreciated.
The details (exim is version 4.63 and running with "-bd -q3m"):
retry_data_expire = 15m
....
begin retry
* * F,8h,3m; F,3d,25m; F,7d,1h
....
send_to_fhg_host:
driver = manualroute
domains = !+local_domains
condition = ${lookup {$domain} dbm
{RELAY_NETWORKS_FILE} {False} {True} }
route_list = * vscanka.fhg.de/MX
transport = remote_smtp
host -t mx vscanka.fhg.de
vscanka.fhg.de mail is handled by 100 mailgw1.fhg.de.
vscanka.fhg.de mail is handled by 100 mailgw2.fhg.de.
vscanka.fhg.de mail is handled by 100 mailgwb1.fhg.de.
The 3 machines are individually taken down and reconfigured fairly often
in a day, so mails get stuck in the queue, presumably if the hints
database marked the specific server as "down":
2006-11-14 07:52:05 Received from xyz@???
H=smtphost.ise.fhg.de (smtphost.ise.fraunhofer.de) [192.168.227.11]
P=esmtps X...
2006-11-14 07:52:06 xxx@??? R=send_to_fhg_host T=remote_smtp
defer (-53): retry time not reached for any host
From "32.8 timeout of retry data" and "44.2 errors in outgoing SMTP" I
assume (wrongly?) the following sequence for a newly arriving mail which
is routed with "send_to_fhg_host":
- MX records are looked up for vscanka.fhg.de, and one IP is choosen.
- this IP is checked with the hints database, if there's a positiv
entry, a connection is never tried and mail gets queued
- at retry time the MX looked is repeated and the same happens again (?)
The last statement would explain why I see mails sitting in the queue
for hours, even with the tight retry times and with one of the 3 IPs
reachable at any given time.
Any insights much appreciated,
TIA1e6
Peter
--
Peter Apian-Bennewitz apian@??? +49-761-4588-[5123|9123]
config & administration for webserver & email
Fraunhofer Institute for Solar Energy Systems, D-79100 Freiburg
"With the right underlying structures and tools, any project can be
reduced to triviality" Marc Crispin