Settings Attributes
In addition to specifying the setting value, you can also set a group of attributes that specify characteristics of the setting. These attributes are as follows:
Overridable/Deployment
These attributes are used to specify whether a setting is fixed or overridable. If selected, the setting is overridable; if cleared, the setting is fixed. The Overridable attribute is only used in Application Designer. For more information, see How to: Specify Application Settings as Overridable. The Deployment attribute is used in System Designer and Logical Datacenter Designer.
In Application Designer, you are working with application definitions — the settings of which can be further customized when an instance of the application is used in a system. If a setting is overridable, then the value of that setting can be changed in System Designer. For example, if you set the Authentication setting for an application to "Forms" and specified that the setting was Overridable, then you can change Authentication to "Passport" on an instance of that application in System Designer.
Note
You cannot override certain settings that contain sensitive data. For more information about these settings, see Considerations for Implementing Applications.
In System Designer and Logical Datacenter Designer, the Deployment check box indicates whether the setting must be used as configured or if it can be changed at deployment. The deployment report generated from a deployment diagram contains a "Fixed" attribute that is set to true or false for each setting that has a Deployment check box. For example, if you want to specify in System Designer that the Authentication setting must be used as configured and cannot be changed at deployment, clearing the Deployment check box sets the "Fixed" attribute to True for the Authentication setting in the deployment report. Selecting the Deployment check box sets the "Fixed" attribute to False, indicating that the setting can be changed at deployment.
Note
Clearing the Deployment check box for a setting in both System Designer and Logical Datacenter Designer indicates that the setting cannot be changed at deployment on the application level or the host level. Though no validation warning will occur, this scenario results in a conflict and must be resolved at deployment.
Null
This attribute specifies whether a setting can have a value of null. If the Null check box is unavailable, the setting value cannot be "Null", and if the default value is "Null", it must be changed. If the Null check box is selected, then the setting value is equal to "Null". If you replace "Null" with another value, the check box clears.
Use Default
This attribute indicates whether the setting value is the default value. All settings have default values (for example, True, Null, Windows, 8080, and so on). If you change the default value for a setting, the UseDefault check box clears. To restore the setting to the default value, select the UseDefault check box. The Use Default attribute is used in Application Designer, System Designer, and Logical Datacenter Designer.
In Application Designer and Logical Datacenter Designer, selecting the Use Default check box changes a modified setting back to its original default value. In System Designer, selecting the Use Default check box changes an overridden setting to the current value on the underlying application or endpoint definition. For more information, see How to: Apply a Setting and How to: Override Application Settings.
Note
If machine.config or web.config settings on your machine differ from the default values specified in software definition model documents provided with the Distributed System Designers (for example, Microsoft.Configuration.sdmDocument for config settings), then the Use Default check box automatically clears and these settings will show up in the search results for overridden settings.
Show in Properties Window
This is an additional attribute for custom settings only. If this value is checked, then the setting is displayed in the Properties window. For more information, see How to: Create Custom Settings for Applications, Servers, Endpoints, and Zones.