The RDN index is referenced whenever a modify, delete, or base search is requested. In other words, the RDN index is needed when the LDAP request contains the complete DN of the targeted entry. If the entry-balancing request processor is not configured to prime the rdn index at startup, then the index is populated over time as LDAP requests are processed.

A global attribute index is an optional index and is referenced when the Directory Proxy Server is handling a search request with an equality filter involving the attribute, such as the telephoneNumber attribute with the filter (telephoneNumber=+11234567890). Since the Directory Proxy Server does not know what the data within the subtree views looks like or how it will be searched, it cannot create or recommend default global attribute index definitions. The creation of a global attribute index is based on the range of equality-filtered search requests that the Directory Proxy Server will handle. The Directory Server must also have an equality or ordering index type for the associated attribute Local DB Index."

The common candidates for global attribute indexing are the uniquely-valued equality-indexed attributes on the external servers. Examples of these attributes are uid, mail and telephoneNumber. Though the values of the attribute need not be unique to be used as a global attribute index by the entry-balancing request processor.

Consider a Directory Proxy Server deployment that expects to handle frequent searches of the form "(&(". Since the filter is constructed with an equality match and &-clause, we can use a global attribute index on the mail attribute to avoid forwarding the search request to each entry balanced dataset.

The following dsconfig command creates the global attribute index. Note that the mail attribute must be indexed for equality searches on each of the external servers behind the Directory Proxy Server.

$ bin/dsconfig create-global-attribute-index \
  --processor-name ou_people_dc_example_dc_com-eb-req-processor \
  --index-name mail --set prime-index:true \

After creating the index with dsconfig, the index will begin to be populated as search requests involving the mail attribute are made to the Directory Proxy Server. At this point, you can also use the reload-index tool to fully populate the index for optimal performance as described in the following section.