Hello all, I wrestled with this "smtp crash" issue for a long time. Others on the list suggested it was the reverse DNS check and/or the Verify HELO/EHLO domain check, and/or any connection checking at all. Only the last suggestion stopped the crashing for me, but not using connection filtering was unacceptable.
I spent a week running through and enabling one blacklist at a time, out of our super-set list of about 18 or so. I started doing this after noticing occasional DNS-BL connect errors in the logs. Eventually, I came across the culprit: dnsbl.ahbl.org. Once I enabled this one, the crashing started again-- 10-20 times a day smtp would go down, often in groupings (rarely here-and-there). Once I disabled it, I continued down my list and was able to enable all the other BL's that we use. I let it run for a week and didn't have a single crash. Then I turned on dnsbl.ahbl.org and had 27 crashes in 24 hours. I disabled it, and we've been crash-free for a week again. This has been a sure-fire fix for the smtp crash issue I've been having. I'm not sure what's causing it, but we have plenty of other lists to utilize and thus can live without this one. I hope this discovery helps others! To Unsubscribe: http://www.ipswitch.com/support/mailing-lists.html List Archive: http://www.mail-archive.com/imail_forum%40list.ipswitch.com/ Knowledge Base/FAQ: http://www.ipswitch.com/support/IMail/
