Below is the complete procedure to setup personal DNS from HELM Control Panel:
HELM support personal DNS for resellers. This means that a reseller can have their own name servers for their domains that is different from the default name servers and other resellers name servers.
The first thing to do is to have the name servers setup up at the domain registrar. Name servers will require their own IP addresses to function correctly. These IPs will need to be added to the server hosting the DNS service and you will need to ensure that the DNS server software is listening on those IPs. Often the DNS server software will listen on all IPs for the server, however, some software doesn't like this and the IPs have to be set manually. See relevant documentation for the server software for more information on how to do this.
To set up the personal name servers, log into HELM as an administrator, go to System Settings" > "Servers", and click on the server that is hosting the DNS service.
Click on the DNS service in the server's service list. At the bottom of the DNS service editor there will be a list of name servers. There should be the "Default" name server(s) already added from when you first created the service.
Click on "Add New" to add the resellers name services. Enter in the relevant information into form and keep "Default name server" unchecked. Click Save to continue.
If you have the primary and secondary DNS service on different machines, you will need to add the secondary name server to the secondary DNS service.
To complete personal DNS, go to the resellers account in Helm and click "Account Settings" under their account. Click on "Global Settings" to get a list of their general Helm settings. On this page there is a Personal DNS Mask box. In this box enter the domain name used for the resellers new name servers. For example. If you have set up ns1.personaldns.com and ns2.personaldns.com then enter "personaldns.com" into the DNS mask. Click Save to save the changes.
Make sure that the mask and the DNS Service name use the same name, or it won't work.
When ever a new domain is now created, Helm will automatically assign these name servers to the domain. You will see them in the Advanced Settings area for the domain.