Suppose I have some domains at GoDaddy/Bluehost/Siteground/wherever.
I set up a Virtualmin on CentOS.
I know that I can point the domain at the VPS's IP, but how does it work if you need to migrate to a site to a different box? Do you have to have the client log in and change their name servers to point at the new box? Is there a way for the VPS provider (Digital Ocean in my case) to handle this or is this a completely manual process?