Forum OpenACS Q&A: Response to ns_sendmail stalls out

Posted by Jun Yamog on
Hi Stan,

I believe qmail has a good queueing mechanism.  Also if your MTA is running through tcp_wrappers it might stop functioning.  For some weird reason tcp_wrappers will detect multiple connections to it as a DOS attack.  This has happened to me, I tried to spam using ns_sendmail but then tcp_wrappers killed port 25 because it thought that it was a DOS attack.

Good luck.