ogletree - 9:27 pm on Dec 17, 2007 (gmt 0)
I assume that if you are moving data centers you will have to get all new ip's. What are you concerned about? Is this related to SEO? The best way to do this is to have the ip's up at the same time. Go ahead and set you DNS TTL to about 3 minutes. This way when you transfer your DNS you don't have much down time. You don't have to worry about IP's being on different subnets unless you are running a bunch of sites that link to each other and are spammy.