Moving from a single IIS to a webfarm using NLB with minimal downtime?

Question

Say the IP of our website is 1.1.1.1, and we want to set up NLB, is it best to set 1.1.1.1 as the virtual IP - could mess this up and cause downtime...

Better to set the virtual IP as 1.1.1.2, then once verified the NLB works, change the DNS to point the A record to 1.1.1.2 instead of 1.1.1.1?

Is there another solution, how would you do this?

Answer 1

Use the second ip. When you are getting ready to make the move lower the TTL on your A record. After the move has been completed successfully you can raise the TTL backup up.