How to set the default nameserver for each reseller ?

Requirement :

Each reseller want their master domain as default nameservers to all the domains which is created under his reseller account.

Solution :

Go to the path,

Home » Resellers » Edit Reseller Nameservers and Privileges

Choose the  reseller and click submit. In the end of the page you can see the  Nameservers block, there you can set the default nameserver for that reseller account.