Using the Web Manager : Web Manager Wizard : Configuring private subnets and virtual addresses

Configuring private subnets and virtual addresses
Figure 6.9 shows the Configure subnets screen that appears when the administrative user selects the Subnets option from the Wizard menu.
Configure Subnets Screen
CAUTION:Changing or deleting an existing private subnet changes the configuration of any device that was previously-configured to use that private subnet; the private subnet is removed from the device’s configuration, and on subsequent attempts to contact the device, the OnBoard appliance tries to use the default route. After changing or deleting a private subnet, to avoid making devices unavailable make sure to reassign all affected devices to the correct private subnet.
Before configuring and assigning private subnets, the site’s administrators must plan an addressing scheme that reflects the needs of the organization. Configuring private subnets is only part of the preparatory work that must be done. On this screen, the administrative user can also configure a virtual network based on Destination Network Address Translation (DNAT).