Using directory assistance in a cluster

A server can use directory assistance to look up information in a directory other than its local primary Domino® Directory. The directory can be a remote LDAP directory or a local or remote replica of any of the following types of Domino® directories: a secondary Domino® Directory, an Extended Directory Catalog, or a primary Domino® Directory. To configure directory assistance, you create a directory assistance database. This database contains information about directories on other servers and how to connect to them.

If you try to access the directory assistance database on a cluster server that is unavailable, Domino® fails over to a replica of the database, if one is available in the cluster. When you use directory assistance in a cluster, be sure you use replicas of the same directory assistance database on all cluster servers that contain a replica. This is important so that Name Lookups fail over correctly.

When the directory assistance database refers to a Domino® directory on a cluster server, you can configure Domino® to use one of two failover methods for directory assistance: directory assistance failover or cluster failover. When you use directory assistance failover, Domino® fails over to one of the servers that you list as having a replica of the directory. Domino® does not take into account the current workload of the servers. When you use cluster failover, Domino® checks the workload of the servers and then fails over to the least busy cluster server that contains a replica of the directory.