When making changes to your network layout, be sure to update the monitoring program as well (e.g. Nagios). If you don’t, and the IPs are different enough, and you wait a while before updating the mail server on the monitoring server…
Well, let’s just say that the queued up E-Mails are still coming in half an hour later, and it’s only for the last three days of “trouble” notifications, though thankfully it’s down to a rate of about one E-Mail per second due to throttling.
