1.3 Overview

  • Article

The Distributed File System: Replication Helper (DFS-R Helper) Protocol provides a set of DCOM interfaces for configuring and monitoring Distributed File System–Replication (DFS-R) on a server, as specified in [MS-FRS2]. The server end of the protocol is a DCOM service that implements the DCOM interface. The client end of the protocol is an application that invokes methods on the interface to make DFS-R configuration changes and monitor the status of the DFS-R service on the server.

The first part of the Distributed File System: Replication Helper (DFS-R Helper) Protocol consists of interfaces for creating, modifying, and deleting configuration objects in Active Directory by using the machine account of the server.

For all replication members, the configuration related to a member is stored in the computer object for the local machine in Active Directory. It is common for system components that are unrelated to DFS-R to set permissions on the computer object that will prevent modification of the object by some users and still permit modification by using the credentials for the computer. Therefore, a server implementation uses the credentials of the local machine account when it sends commands to update Active Directory objects.

If a user has sufficient privileges to connect to the server that is running the DFS-R Helper Protocol and to invoke methods implemented by the DFS-R Helper Protocol interfaces, the server works as a proxy for making configuration changes on behalf of the client application that is running under the user's account.

The client sends the server information about the Active Directory operation that the client is trying to accomplish. The server then attempts to execute the command by using the machine account and returns information about the status of the operation.

The second part of the Distributed File System: Replication Helper (DFS-R Helper) Protocol is an interface for monitoring DFS-R on the computer and collecting various statistics about the DFS-R operation.

The information that is collected by using the Distributed File System: Replication Helper (DFS-R Helper) Protocol includes, among other types of information, the following statistics:

  • Information about replication errors that are encountered by DFS-R on the server.

  • The count and size of replicated files on the server.

  • Disk use on the server.

  • Information about replicated folders on the server.

  • Replication backlog—the number of files that are not yet fully replicated.

Sections 2 and 3 specify the Distributed File System: Replication Helper (DFS-R Helper) Protocol and define protocol messages, their parameters, and the XML format of the health report.