.. _network_device_list_selection_rules:

Network Device List Selection Rules
-----------------------------------

If an administrator at a hierarchy has access to more than one Network Device
List (NDL), the option to choose a specific hardware group or list may be needed
in order to provision a set of devices.

The Rule Model Device Selection Type model provides a solution to this problem
and instances of it are a set of rules for views and relations at a hierarchy
level. A particular NDL can then be selected from a popup form before the Add
form of these model types are shown. In this way, the administrator can then
select the specific required NDL.

When an instance of the Rule Model Device Selection Type model is added, the
target relation or view is specified and more than one set rules can be added for
it - one for each relevant Hierarchy Node Type.

In addition, a Default GUI Rule that is applied to the Relation or View is
reflected as the Default value for the Permitted Hierarchy Node Type.

In addition to this behavior, these rules apply:

* The NDL popup is only available for Relations and Views.
* Device form fields are filtered according to the device listed in the selected
  NDL.
* More than one type of device is supported for the selected NDL.
* Any Provisioning Workflow Network Device Filters (NDF) override a selected NDL
  device choice.
* Only the Add operation supported.
* For details on NDL popups, refer to the topic on Network Device List Selection Rules Advanced Configuration
  in the Advanced Configuration Guide.