Mass DNS Update
Begin by Logging in to Your Account and navigating to your "My Domains" tab. Next, check off the domains that you want to update, and then click on the "With Selected" drop down box at the bottom of the domain list, as shown here:
Enter New DNS Servers
Now you can enter the DNS servers you wish to use for all of the selected domains. Enter your custom servers, or select to use our "default nameservers" if you wish to park or forward the domain.