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When you change your nameservers to point to Cloudflare, some domain registrars (e.g. GoDaddy) ask you to provide the IP address of the nameservers alongside them.
You can find the IP address needed with an online tool, or a command. Multiple IP addresses may be returned for each nameserver, it should not matter which you use.
Using an online tool
You can use an online tool to find the IP address of your Cloudflare nameserver.
One example is digwebinterface.com, you can just enter your two Cloudflare nameservers (as in the example below) and click ‘Dig’, the tool will then return the IP address for each nameserver.
An alternative is dnschecker.org, you can just enter the nameserver, make sure the dropdown shows A and click search. Regardless of the approach (e.g., dig, dnschecker, et al), you’ll see three IP addresses for your name servers, pick one and enter it where you are asked IP address.
Using the command line
Windows 10
To open the terminal:
Click the start icon 
Type cmd and click to open the ‘Command Prompt’ 
The command
To see the IP address of the Cloudflare nameserver, we will use a command called nslookup. Enter this in your command line:
nslookup name.ns.cloudflare.com replacing name.ns.cloudflare.com with your first Cloudflare nameserver. Then press enter/return to run the command.
You will get a response that looks something like:
Server: one.one.one.one
Address: 2606:4700:4700::1111
Non-authoritative answer:
Name: name.ns.cloudflare.com
Addresses: 2001:0db8:85a3:0000:0000:8a2e:0370:7334
192.0.2.1
This will give you the IP addresses of the nameserver. The one you most lilely want is the IPv4 address which is the second one in the format 192.0.2.1 in the example above. Just repeat the process for your second nameserver.
Mac
To open the terminal:
The Terminal can usually be found under Applications > Utilities and will look something like: 
The command
To see the IP address of the Cloudflare nameserver, we will use a command called dig. Enter this in your command line:
dig A name.ns.cloudflare.com +short replacing name.ns.cloudflare.com with your first Cloudflare nameserver. Then press enter/return to run the command.
You will get a response that looks something like this:
192.0.2.1
This will give you the IP addresses of the nameserver. Just repeat the process for your second nameserver.
Linux
To open the terminal:
Opening the terminal will vary on different linux distributions, however the icon normally liiks something like: and often appears on the dock or under ‘Administration’ in the menu.
You can also use the shortcut Ctrl + Alt + T.
The command
To see the IP address of the Cloudflare nameserver, we will use a command called dig. Enter this in your command line:
dig A name.ns.cloudflare.com +short replacing name.ns.cloudflare.com with your first Cloudflare nameserver. Then press enter/return to run the command.
You will get a response that looks something like this:
192.0.2.1
This will give you the IP addresses of the nameserver. Just repeat the process for your second nameserver.
Note: This tutorial contains links to external resources over which we have no control. As always, any commands you run on your own device are at your own risk.
Tutorial Reference: CT-45
Reviewed: 07/21
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