From Bugzilla Helper: User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4) Gecko/20031212 Description of problem: when lots ( > 3000) of mails come to the maildrop queue the pickup daemon hangs, sometimes the master daemon pick that situation and make a restart to pickup daemon but sometimes it doesn't, when it doesn't all the mail flux stop because nobody move mails from maildrop to incoming queue. you have to restart postfix by hand to fix the situation here is some of pickup logs: Feb 23 14:46:44 mail postfix/pickup[4800]: fatal: watchdog timeout Feb 23 15:03:28 mail postfix/pickup[18406]: fatal: watchdog timeout Feb 23 15:21:08 mail postfix/pickup[28746]: fatal: watchdog timeout Feb 23 15:38:48 mail postfix/pickup[486]: fatal: watchdog timeout Feb 23 15:56:28 mail postfix/pickup[4631]: fatal: watchdog timeout Feb 23 16:14:11 mail postfix/pickup[9811]: fatal: watchdog timeout Feb 23 16:31:54 mail postfix/pickup[15322]: fatal: watchdog timeout Feb 23 16:49:36 mail postfix/pickup[21637]: fatal: watchdog timeout Feb 23 17:07:16 mail postfix/pickup[25701]: fatal: watchdog timeout Feb 23 18:07:11 mail postfix/pickup[32112]: fatal: watchdog timeout Feb 23 18:24:53 mail postfix/pickup[7754]: fatal: watchdog timeout Feb 23 18:42:36 mail postfix/pickup[22061]: fatal: watchdog timeout Feb 23 19:00:17 mail postfix/pickup[10177]: fatal: watchdog timeout Feb 23 19:18:03 mail postfix/pickup[31180]: fatal: watchdog timeout with each line you can find two more from master process Version-Release number of selected component (if applicable): postfix-2.0.11-4 How reproducible: Always Steps to Reproduce: 1. send a bunch of e-mails to maildrop queue (using mail command for example), more than 10 000 will be ok 2. keep feeding the maildrop queue faster than the postfix speed 3. keep looking in to pickup activity (tail -20f /var/log/maillog | grep pickup) Actual Results: after 17-18 minutes, if you still have more than a few thousand of mail in the maildrop, you start getting the fatal error. those errors will apear very regulary, after 17-18 minutos from eachother, when someone fail to apear is because: 1. there is less than 1000 mails in the maildrop 2. the pickup hangs and the master couldn't notice that, pickup will never pick anymore mail from maildrop until restarted by hand Additional info: as i say, if the pickup daemon hangs and the master didn't notice that, the mail system for uucp peoples, and any other solution where the e-mail are passed to the postfix system by direct invocation of the sendmail command (webmail, smtpd-obtuse, etc) will be stopped. the mails will start acumulating into maildrop queue waiting for the pickup daemon, the mail queue could become very large in busy servers.
If you edit /etc/postfix/master.cf and change the line pickup fifo n - n 60 1 pickup to pickup fifo n - n 60 1 pickup -v it should give additional debugging information to show why pickup is hanging
This is probably the bug described here http://www.irbs.net/internet/postfix/0401/2658.html
Have you tested if the patch from comment #2 is solving your problem?
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