Modifying unassigned (unmanaged) control network interface

The system description must have a placeholder device for the computer with the control network connection.
The placeholder device must have one or more unmanaged network interfaces.

In the Network Configuration | Devices tree view, select the placeholder device for the computer with the control network connection.
The interfaces for that device are displayed in the interfaces list view.
Edit the control network interface first.
In the interfaces list view, right-click the control network interface and select Edit.
The Unmanaged Network Interface Details dialog box opens.

Configure the settings for the interface as follows:

Setting...	For control network interface
Network	Control is required
IP Address	The IP address for this interface on the network. Required.
Interface Name	The device host name. Required.
Set to Default	Not recommended. Sets the interface name to SiteConfig default convention, based on the root Site name and device-type.
...use Interface Name/Aliases in Host Files...	Unselected is required. Since not selected, the default behavior occurs, which is to use the device host name in the hosts file.
Aliases	Not allowed
DNS Suffix	Allowed, if applicable to the network. The DNS suffix is added to the interface name.