Hi, I'm about to do a mail server migration. This is a hardware upgrade, i.e. the software will remain pretty much the same (qmail,vpopmail,bincimap,qpsmtpd, etc).
I'm thinking about how best to do the cutover between mail servers. At some stage, I want to stop mail being delivered to server A and have it delivered to server B. But, there will be period of time while the DNS changes propagate where mail could potentially be delivered to server A and server B (different messages, obviously). Is this correct? If so, I've been thinking of how best to re-direct any connections arriving at server A over to server B. Any suggestions? All comments appreciated. Thanks, R.
