Sign in to your Dynadot account. Select "Manage" from the "Domains" drop-down menu. Check the box next to your domain name(s) and click on the "Name Servers" icon. Click on the "Name Servers" tab. There are two ways to set your name servers:
To add new name servers, look at Option 1. Enter your two name servers in the provided text boxes, and then click the "Enter Name Servers" button to save your changes. If you have already entered the name servers for another domain and would like to re-use them, look at Option 2. Choose the name servers from the drop-down menus (you can choose up to 10 different name servers), and then click the "Select Name Servers" button to save your changes.
source : Dynadot support
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Select "My Domains" from the left-side menu bar and click "Manage Domains" in the drop-down.
Check the box next to your domain name(s) and click on the "Action" button.
Choose "DNS Settings" from the "Action" list.
On the DNS page, select the "Name Servers" setting from the top drop-down menu.
There are two ways to set name servers: - If you are adding new name servers, select "Enter new or existing Name Servers" from your list of choices and enter your new name servers in the provided fields. - If you are using existing name servers, move down to the "Select from your Name Servers" option and choose the name servers from your existing list.
Press the "Save Name Server" button to save your changes.
Please be aware that it might take some time for your name server changes to propagate.
Alternatively, you can also set your Name Servers when transferring your domain. To do so, while your item is in the cart, please click on the hardware icon. It will prompt you through a short two step wizard and guide you through the set up process.