Stanislav Sinyagin wrote:
We use the email greylisting policy for incoming email for us and our customers, and it appears that often the email from Sunrise network comes with huge delays, from several hours to several days.
Did anyone else see such problems? Guys from Sunrise, plase contact me directly for more details and troubleshooting.
Just a guess: The more retries to a certain SMTP destination, the longer the retry interval...leads to exponential delivery times.
Pure greylisting is - just like blacklistsing - is useless or leads to unexpected behavior without a well-maintained and monitored whitelist for a corporate or ISP e-mail system.
Up to each engineer what he is using for his own private or business server - but this is a different pair of shoes.
-Kurt.