## Creating a Read-Only Replica

From time to time, you will want to create read-only replicas of directories. You create read-only replicas of a directory for the following purposes:

· To distribute the information that is contained in the directory throughout your network, and to make the information more accessible to users and applications at other locations.

· To improve response time, especially in a namespace where users are dispersed over long distances. You should create read-only replicas in clearinghouses that are located near the user groups and applications that most frequently use the information that is contained in the directory.

· To preserve a backup of the information that is contained in the master replica of the directory. Maintaining multiple replicas ensures that the temporary loss of an individual replica does not cause an interruption in service and that the loss of a replica can be easily recovered. Even directories that store information used at only one particular site should be replicated in at least one other clearinghouse, preferably on a server at another location, so that a local failure at one site does not cause both replicas to be unreachable at the same time. (See Managing Clerks, Servers, and Clearinghouses for more information on using directory replication as a means of backing up CDS information.)

Read-only replicas of directories are safe from alteration by users. Users can look up information in a read-only replica, but they are not permitted to create new information or modify existing information.

You create read-only replicas with the -replica option of the directory create command. You should create the replicas in clearinghouses whose users need to access the directory but do not need, or are not permitted, to update its contents.

More:

Before You Create a Replica

Permissions for Creating Replicas

Entering the directory create Command

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