Sun Cluster 3.1 Data Services Developer's Guide

Default Property Values

The RGM stores all resources such that any property that was not explicitly set by the system administrator (and which was defaulted) is not stored in the resource CCR entry. The RGM obtains the default value of a missing resource property from the resource type (or if not defined there, using a system-defined default) when a resource is read in from the CCR. It is this method of storing properties that permits an upgraded resource type to define new properties or new default values for existing properties.

When resource properties are edited, the RGM stores in the CCR the properties that were specified in the edit command.

If an upgraded version of the resource type declares a new default value for a defaulted property, the new default value is inherited by existing resources, even if the property is declared tunable only At_creation or When_disabled. If the application of the new default would cause a method such as Stop or Postnet_stop or Fini to fail, the resource type implementor must accordingly restrict the state of the resource at the time that it is upgraded. This is done by limiting the tunability of the Type_version property.

The new resource type version Validate method can check to make sure that existing property attributes are appropriate. If they are not, the system administrator can edit the properties of an existing resource to appropriate values in the same command that edits the Type_version property to upgrade the resource to the new resource type version.

Note –

Resources that were created in Sun Cluster 3.0 do not inherit new default property attributes from the resource type when they are migrated to a later version because their default properties are stored in the CCR.