I have a dedicated server with about 50 domains running on it. I am replacing the server and migrating everything to the new one. About half the domains are controlled by me in my enom account, where the server domain and dns domains are registered. The rest of the domains are controlled by clients so they could be registered anywhere.

If I change the DNS IP addresses at enom, will this be all that is needed, or do the clients have to also update the custom DNS ip addresses with their registrar. I thought in the past that I had to do this, but I have an account at WildWest with a couple of domains in it and when I tried to change the DNS IP, there was no place to do it for DNS domains registered elsewhere. I called support and they said that all I didn't need to do anything. This doesn't sound right because I could have sworn that the last time I switched servers (several years ago), that I had to go into an account I had at GoDaddy and redefine the IP address of the server for the custom DNS, even though the server/DNS domain was at Enom.

Trying to avoid a total disruption to my clients, can someone tell me if this is correct. Is it as simple as me changing the ip address of DNS at Enom in one place and being done with it?

If all those domain names use the exact pair or so of nameservers, just change the IP addresses of the nameservers where the parent domain name is registered with. By parent domain name, I mean the one you have control over.

Let's say clientdomain1.com, clientdomain2.com and clientdomain3.com all use ns1.yourdomain.com. The parent domain name of ns1 is yourdomain.com that you control inside your eNom account.

Log inside your eNom account and change the IP address of ns1.yourdomain.com. It'll eventually be picked up by any domain name using that nameserver no matter what registrar they're with. (well hopefully, anyway...)

Makes sense? Anyone feel free to correct me if I'm wrong somewhere, and this is based on what the OP has stated so far.

I'd agree with that. You should only need to change the clients' domains at their registrar if they use their own custom nameservers - nsx.clientdomain.com - normally only resellers would have this.

The other thing I'd do is keep the old server up for as long as possible after you make the switch and copy the new zone files over to it. That way anyone connecting to the old nameservers will still be directed to the new server, and they should also pick up the change in nameserver IPs.

I wish I had found this thread yesterday!

I've been going through the same thing this past week, I changed the IP's of my nameservers on Monday night but they haven't been picked up yet.

Anyone know how long it usually takes for the new nameserver IP's to be picked up?

I've also still got the old server up and running and will have for another couple of weeks, would editing the DNS zone on the old server redirect users to the new one?

Cheers,
Dan

For most users it usually happens within hours, there are just a few ISPs that cache records for way too long.

If many people are still going to the old server after several days I would guess your setup's wrong. Did you change the IPs of your nameservers in your zone file as well as at your registrar? Check it with dnsreport.

I've also still got the old server up and running and will have for another couple of weeks, would editing the DNS zone on the old server redirect users to the new one?Yes, but if the setup's wrong and you're still telling people to use the old nameservers you'll have a problem when you turn the old server off.