To add or modify a DNS server delegation, you must access the domain management from the "Basic list of services" in the control panel of cdmon.
On the domain management screen you must click on the option Manage delegations.
From "Manage delegations" you can manage the delegations you have created or create new ones by clicking on Create delegation.
In the "Create DNS delegation" form you can create subdomains that will be registered as DNS server records.
To do so, you must complete the following fields:
Once you have entered the data in the corresponding fields, you must click on Save changes. Remember that any DNS server change has an approximate propagation time of 24 hours.