I currently have a few websites hosted with a web host, but I want to switch to a better host. I found one that I want to use on a trial basis, transferring one website at a time to it to see how well it works for me before committing fully. Both hosts are shared servers, and I have one primary domain and three add-on domains. All four domains are registered through a third party and I point the name servers to the older host.
My question is, would I likely run into a problem if I were to point the nameserver for the add-on domain before the primary domain? Or vise-versa? For example, if I make an account with the new host and select my existing primary domain as what will be the main domain for the account, but keep the name servers pointed at the old host, would that cause issues? Because, for example, for these servers
www.addondomain.com is usually also the same as
addondomain.example.com but that latter address wouldn't actually work without
example.com being set up.
Or alternatively, if I transfer the name server for the primary domain to the new host before doing so for the add-on domains, might that cause the add-on domains to stop functioning?
To be clear, the domain registrar is staying the same. The web host is what will be changing.
Potentially this is something that the new web host can answer, but I'm looking for a little grounding so I can ask the right questions.