System Administration Guide: Naming and Directory Services (NIS+)

Lagging or Out-of-Sync NIS+ Replica

When you create or modify an NIS+ object, there is a time lag between the completion of your action and the arrival of the new updated information at a given replica. In ordinary operation, namespace information may be queried from a master or any of its replicas. A client automatically distributes queries among the various servers (master and replicas) to balance system load. This means that at any given moment you do not know which machine is supplying you with namespace information. If a command relating to a newly created or modified object is sent to a replica that has not yet received the updated information from the master, you will get an “object not found” type of error or the old out-of-date information. Similarly, a general command such as nisls may not list a newly created object if the system sends the nisls query to a replica that has not yet been updated.

You can use nisping to resync a lagging or out of sync replica server.

Alternatively, you can use the -M option with most NIS+ commands to specify that the command must obtain namespace information from the domain's master server. In this way you can be sure that you are obtaining and using the most up-to-date information. (However, you should use the -M option only when necessary because a main point of having and using replicas to serve the namespace is to distribute the load and thus increase network efficiency.)