Tarragon Allen wrote:
On Tuesday 21 October 2003 13:43, Rod Rodolico wrote:Guess is boils down to this. When I update the address of mail.dailydata.net, it can take up to 72 hours for that change to perculate throughout the net, so I'm assuming some places will still try to send to the old IP and, if I leave that box on, be delivered to it. If I turn the other box off, I'm assuming they will bounce.
No they won't bounce; most mailservers will leave messages in their queues for up to 5 days when your machine is down. If you lower the TTL for mail.dailydata.net it shouldn't take 72 hours either.
Put the IP address of the old site on the new mail server when you bring down the old one, and then change your DNS entry, wait three days, then drop the old IP address. Alternatively, set up a redirector on the old mail server to forward traffic to the new mail server (using 'redir' or something similar).
Or even easier: assuming the machines are in the same subnet, why not add the IP address of the old server to the new one, on eth0:1 or any other alias for your primary NIC?
Both traffic to the old and the new IP will end up on the right server, and you can easily back out if there is a problem by removing the alias.
Maarten Vink