changstrom wrote:
In other words, couldn't some person set notmydomain.com, if the NS was set to Linode's DNS servers, to point to their own ip?
Yes. But only if the owner of notmydomain.com hadn't already created a zone in the Linode DNS Manager, which would be fairly silly. You can create any domain you want in the Linode DNS Manager as long as it isn't already in there. I'm not encouraging you to, just pointing out that you can. We can't verify ownership of a domain in any consistent way, as that doesn't scale and there's a billion cases where it wouldn't work.
If someone were to add jedsmith.org to, say, ZoneEdit or some other DNS provider, they could certainly add it and populate it with records -- however, when someone types "jedsmith.org" in their browser, the domain name system (and my registrar) says who is
really the guy to ask about jedsmith.org. You could still get the bad records if you used dig to ask
directly, but not in the general case. Were I ever to sign up with ZoneEdit, I would have to file a ticket with them and prove ownership before I could use their service, I guess.
So, ns1.linode.com is probably authoritative for all kinds of domains that aren't pointed at it, either through the passage of time (and people forgetting to delete zones when they move the domain) or genuine malice, which would be pretty pointless in the grand scheme.
If a domain is pointed at ns1.linode.com and friends, a responsible domain operator should have the zone populated beforehand. If someone has created your domain in our system already,
before you point the domain at our nameservers file a ticket and we'll look into it. It's all in where the domain is pointed, and you cannot create duplicate zones in the Linode Manager (which is what I think you might be getting at).