Oh, to add more details: I tried writing test code which would loop and call mail(). Wether I did 20 or 50 iterations, or even running two of the page that did 50 at the same time, to a local address, it still all worked. I also tried sending 50 to "test@invalid.invalid" (since I didn't want it to bother a real host), and it didn't report any errors at the mail() function. So it's obviously not just a "number of messages being sent" thing-- the only thing I could see is to somehow monitor all 100+ sites hosted on the server to see if something hits a critical point. -----Original Message----- From: fouldragon@aol.com To: plug-discuss@lists.plug.phoenix.az.us Sent: Wed, 11 Jun 2008 5:44 pm Subject: PHP mail() woes Several sites on the VPS I administer send out several "order confirmation" emails when a specific page is hit. Because of the way they run their businesses, it's non-negotiable that between 3 and ~12 messages are sent out on these occurences. The problem is that occasionally--- probably about one in 20 times such a page is accessed, the server error logs fill up with: [Wed Jun 11 13:38:06 2008] [error] [client a.b.c.d] PHP Warning: mail() [function.mail]: Could not execute mail delivery program '/usr/sbin/sendmail -t -i' in /var/www/vhosts/xxxxxxx/httpdocs/feedback.php on line 54, referer: http://xxxxxxxx Since it tries to send a handful of messages at once, they usually come in clumps of 5 or 6 messages like this. I tried correlating the times of the errors with resource warnings in Virtuozzo; no dice. I keep hearing that the PHP mail() call is not intended for bulk mailing-- but less than 20 messages at a shot is not bulk as I see it. The only thing I could see is some sort of resource exhaustion... like it can only have xxx mail() calls in the air at once, and it exceeds that limit. The server runs FC6 with Plesk 8.3 on top, so the mail setup is qmail, but it uses xinetd. I saw a few notes about being able to tweak qmail-smtpd to open more instances, but I'm not even sure that's relevant to the problem (since mail() calls are coming from local). What about replacing /usr/sbin/sendmail -t -i with /var/qmail/bin/qmail-inject - someone suggested this? Would that have any possible difference? And what's a good way to find out if this will repeat, other than sitting and monitoring the logs for an error? --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us To subscribe, unsubscribe, or to change your mail settings: http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss