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.