Creating the CoS Definition Entry From the Command Line

All CoS definition entries have the LDAPsubentry object class and inherit from the cosSuperDefinition object class. In addition, each type of CoS inherits from specific object classes and contains the corresponding attributes. The following table lists the object classes and attributes that are associated with each type of CoS definition entry.

In all cases, cosAttribute is multivalued. Each value defines an attribute that is generated by the CoS mechanism.

You can use the following attributes in CoS definition entries. For more information about each of these attributes, see the individual attributes in Sun Java System Directory Server Enterprise Edition 6.3 Man Page Reference.

You cannot use the isMemberOf attribute as a CosSpecifier to make all the members of static groups automatically inherit from a common computed attribute value.

The cosAttribute attribute allows two qualifiers following the name of the CoS attribute, the override qualifier and the merge qualifier.

The override qualifier describes the behavior when an attribute that is dynamically generated by CoS already physically exists in the entry. The override qualifier can be one of the following:

• default (or no qualifier) - Indicates that the server does not override a real attribute value stored in the entry when the attribute is of the same type as the computed attribute.

• override - Indicates that the server always returns the value generated by the CoS, even when a value is stored with the entry.

• operational - Indicates that the attribute will only be returned if it is explicitly requested in the search. Operational attributes do not need to pass a schema check to be returned. The operational qualifier has the same behavior as the override qualifier.

  You can only make an attribute operational if the attribute is also defined as operational in the schema. For example, if your CoS generates a value for the description attribute, you cannot use the operational qualifier because the description attribute is not marked operational in the schema.

The merge qualifier is either absent or merge-schemes. This qualifier allows the computed CoS attribute to be multivalued, either from multiple templates or multiple CoS definitions. For more information, see Multivalued CoS Attributes.

Overriding Real Attribute Values

You might create a pointer CoS definition entry that contains an override qualifier as follows:

dn: cn=pointerCoS,dc=example,dc=com
objectclass: top
objectclass: LDAPsubentry
objectclass: cosSuperDefinition
objectclass: cosPointerDefinition
cosTemplateDn: cn=exampleUS,cn=data
cosAttribute: postalCode override

This pointer CoS definition entry indicates that the entry is associated with the template entry cn=exampleUS,cn=data that generates the value of the postalCode attribute. The override qualifier indicates that this value takes precedence over the value of the postalCode attribute if the attribute exists in a target entry.

If the CoS attribute is defined with the operational or override qualifiers, you cannot perform write operations on the “real” value of that attribute in any entry in the CoS scope.

Multivalued CoS Attributes

When you specify the merge-schemes qualifier, the generated CoS attribute can be multivalued in two ways:

• With indirect or classic CoS, the specifier attributes in target entries can be multivalued. In this case, each value determines a template, and the value from each template is part of the generated value.

• Multiple CoS definition entries of any type can contain the same attribute name in their cosAttribute. In this case, if all definitions contain the merge-schemes qualifier, the generated attribute contains all values computed by each definition.

The two situations can occur together and define even more values. However, in all cases, duplicate values will only be returned one time in a generated attribute.

In the absence of the merge-schemes qualifier, the cosPriority attribute of the template entry is used to determine a single value among all templates for the generated attribute. This scenario is described in the next section.

The merge-schemes qualifier never merges a “real” value that is defined in the target with generated values from the templates. The merge qualifier is independent of the override qualifier. All pairings are possible, and the behaviors implied by each are complimentary. Also, the qualifiers can be specified in any order after the attribute name.

When there are multiple CoS definitions for the same attribute, the definitions must all have the same override and merge qualifiers. When different pairs of qualifiers occur in CoS definitions, one of the combinations is selected arbitrarily among all definitions.

CoS Attribute Priority

If multiple CoS definitions or multivalued specifiers exist, but no merge-schemes qualifier, Directory Server uses a priority attribute to select a single template that defines the single value of the computed attribute.

The cosPriority attribute represents the global priority of a particular template among all those being considered. A priority of zero is the highest priority. Templates that contain no cosPriority attribute are considered the lowest priority. When two or more templates provide an attribute value but have the same or no priority, a value is chosen arbitrarily.

Template priorities are not taken into account when using the merge-schemes qualifier. When merging, all templates being considered define a value regardless of any priority that the templates define. The cosPriority attribute is defined on CoS template entries as described in the following section.

The cosPriority attribute must not have a negative value. Also, attributes generated by indirect CoS do not support priority. Do not use cosPriority in template entries of an indirect CoS definition.