Is it normal for nameservers to keep switching back and forth from the old IP, to the new IP you want to set it too?
For example, if someone has a reseller account, and they have their own private nameservers, and later they move to a whole different company or new server, how long does it take for those nameservers to update to the new server's IP, and is it normal if you keep pinging the IP that it goes back and forth like it "can't make up it's mind" what it wants to do
Lastly, does it take the full 24-48 hours to switch or..?
Thanks guys, a friend needed to know this information.
Depending on where you're checking it from, it can happen. Although you might have a certain TTL set on your nameservers, ISP's don't always honor your settings. So for some people, the switch will be quick, while for others on crappy ISP's, name resolution won't update for sometimes up to 3 days or possibly even more. But the longest I've ever seen is 72 hours and it's usually some goofy ISP from canada or australia.