I am planning to change the web host of one of my web sites, and the site has a webmail service (similar to Hotmail, etc.). I recall that when I first set it up, I had to edit the MX record in the DNS file.
Before I change the web host of this site, I am wondering, what is the DNS file? Is this a file posted on the server of the web host (in which case I would have to transfer it to the new host)? Or is this a file hosted on a server of the company through which I registered the domain (in which case, I might not have to do anything)?
Is maintaining and editing the DNS file going to be a big deal?