Directory Replication

Within a site, you don't need to plan directory replication because all directories are automatically synchronized. However, you do need to plan and configure directory replication between sites, beginning with these steps:

1. Determine your directory replication topology.
2. Identify the replication bridgehead servers.
3. Determine a schedule for directory replication.

The directory replication topology affects the time it takes to fully replicate directories. Because it is difficult to change your directory replication topology after it's in place, careful planning is important. Your topology must include all sites in your organization. It will grow with your organization as new sites are added. Your topology should also minimize the number of sites through which messages are replicated.

In addition, your replication topology should map to your messaging topology so that directory replication messages travel on the least costly connections.

You should also decide how many bridgehead servers to configure for each site. If you have many sites, consider balancing the load among servers by choosing a different bridgehead server for each remote site. You can add bridgehead servers as new sites are added. When you configure directory replication, remember that replication generates message traffic.

You also need to determine when directory information should be exchanged with other sites. The directory replication schedule is based on how often your organization needs an updated directory. If replication occurs too frequently, bridgehead servers won't be able to receive and process replication messages before they request new updates. This results in redundant requests.

If two sites are connected through a slow connection, schedule directory replication between these two sites so that the slow connection is used only occasionally. This minimizes the use of that connection and improves performance.