Dear Community Friends Greetings,
i work with ISP, we host email service for almost 500+ companies and 200+ mail servers relay through my smart host.
i implemented something that when our smart host would become blacklisted. It will automatic switch to next available smart host (which is ready sitting). that mean it will start relaying message through another smart host automatically.
i think i must tell little background as well. it is actually php script that perform blacklist check every minute through cron. if it found that IP is blacklisted. It will then insert "relay host =" value in main.cf and reload postfix service. When IP is no more blacklisted it will then remove the same directive from main.cf and reload postfix.
everything is working as expected. i have one question, when we reload postfix does it drop active SMTP session?
for example lets say that remote SMTP server is delivering message to my postfix that has 8MB attachment. message was not fully transferred. lets say that 4MB was transferred. and i issued "postfix reload". will that connection drop or continue to deliver the mail?
Thanks / Regards Prabhpal S. Mavi