Should your reseller require private nameservers, you can set these up from within your master reseller control panel.
- Login to Master Reseller CP
- Click on 'Resellers
- Click on 'List Resellers'
- Click on 'Options'
- Click on 'Limit & private NS'
- Scroll down to the private nameservers section
- Add the nameserver addresses (eg - ns1.yourdomain.com)
- Click on 'Submit'