As I reported via Twitter late last week, we encountered an issue that got some of our mail delivery delayed by about a day and a half. I’ll explain more about what happened as I believe in openness on these matters, and also the experience has educational content for others.
Our mail server doesn’t have direct external interaction, it’s shielded by two relays that handle both the inbound MX and the outbound queue. This setup works remarkably well in terms of exposure to spam and other malicious activity. As previously discussed, it appears that it’s more difficult to make mail server infra more resilient without expending lots more time/effort and …[Read more...]