5.3. About Classes of Service
facsimileTelephoneNumber. Traditionally, to change the fax number required updating each entry individually, a large job for administrators that runs the risk of not updating all entries. With CoS, the attribute value can be generated dynamically. The
facsimileTelephoneNumberattribute is stored in one location, and each entry retrieves its fax number attribute from that location. For the application, these attributes appear just like all other attributes, despite not actually being stored on the entries themselves.
- The CoS definition entry identifies the type of CoS. It is stored as an LDAP subentry below the branch it affects.
- The template entry contains a list of the shared attribute values. Changes to the template entry attribute values are automatically applied to all the entries sharing the attribute.The CoS definition entry and the template entry interact to provide attribute values to their target entries, the entries within their scope. The value they provide depends upon the following:
- The entry's DN (different portions of the directory tree might contain different CoS).
- A service class attribute value stored with the entry.The absence of a service class attribute can imply a specific default CoS.
- The attribute value stored in the CoS template entry.Each CoS template entry supplies the attribute value for a particular CoS.
- The object class of the entry.CoS attribute values are generated only when an entry contains an object class allowing the attribute when schema checking is turned on; otherwise, all attribute values are generated.
- The attribute stored in some particular entry in the directory tree.
5.3.1. About a Pointer CoS
Figure 5.1. Sample Pointer CoS
cn=exampleUS,cn=data, in the CoS definition entry. Each time the
postalCodeattribute is queried on the entry
cn=wholiday,ou=people,dc=example,dc=com, the Directory Server returns the value available in the template entry
5.3.2. About an Indirect CoS
Figure 5.2. Sample Indirect CoS
managerattribute. William's manager is Carla Fuentes, so the
managerattribute contains a pointer to the DN of the template entry,
cn=Carla Fuentes,ou=people,dc=example,dc=com. The template entry in turn provides the
departmentNumberattribute value of
5.3.3. About a Classic CoS
Figure 5.3. Sample Classic CoS
cosSpecifierattribute specifies the
employeeTypeattribute. This attribute, in combination with the template DN, identify the template entry as
cn=sales,cn=exampleUS,cn=data. The template entry then provides the value of the
postalCodeattribute to the target entry.