I am looking for a good approach to this scenario.

I have a particular site that some of my customers connect to every 60 seconds and call a Web Service.

I am in the process of planning the upgrade to a new server.

I have 2 options:

1. I can simply switch the IP address of the domain to the new server when I deactivate the old server. This is an easy solution, but seems like it may be too easy, and since I have to involve a tech team on the other side of the country, if I need to change back (if things go sideways), then it may get a bit more complicated.


2. Register the second IP Address with the domain's DNS A record a few days in advance, then simply turn off the old server. For this one, I am not sure how the DNS switch will be recognized the the client's server that calls the WSO on our server. The Client side is set up as a Windows Service that constantly runs and only restarts when the client's server is rebooted.

I see option #1 as a quick and dirty way to get the job done, but a little bit "hack-ish". I'd love to hear ideas about how others would handle this.