DFS Namespaces and DFS Replication Overview

Applies To: Windows Server 2012 R2, Windows Server 2012

This topic discusses the DFS Namespaces (DFSN or DFS-N) and DFS Replication (DFSR or DFS-R) role services, which together comprise Distributed File System (DFS) in Windows Server 2012 R2 and Windows Server 2012. This topic discusses how to install DFS, what’s new, and where to find evaluation and deployment information.

Did you mean…

• What's New in DFS Replication and DFS Namespaces in Windows Server

• DFS Management (online Help)

• DFS Step-by-Step Guide for Windows Server 2008

• DFS Replication: Frequently Asked Questions

• DFS Namespaces: Frequently Asked Questions

Role service descriptions

DFS Namespaces and DFS Replication are role services in the File and Storage Services role.

• DFS Namespaces   Enables you to group shared folders that are located on different servers into one or more logically structured namespaces. Each namespace appears to users as a single shared folder with a series of subfolders. However, the underlying structure of the namespace can consist of numerous file shares that are located on different servers and in multiple sites.

• DFS Replication   Enables you to efficiently replicate folders (including those referred to by a DFS namespace path) across multiple servers and sites. DFS Replication uses a compression algorithm known as remote differential compression (RDC). RDC detects changes to the data in a file, and it enables DFS Replication to replicate only the changed file blocks instead of the entire file.

Practical applications

You can use DFS Namespaces and DFS Replication to achieve the following goals:

• DFS Namespaces   Provide users with a centralized folder namespace through which to access and store files. You can host the underlying file shares on different servers and in different sites to improve availability and performance.

• DFS Replication   Synchronize folder contents efficiently between servers, across LAN or WAN network connections.

New and changed functionality

The following table describes the changes in DFS Namespaces and DFS Replication functionality.

For more information about what’s new in DFS Replication in Windows Server 2012 R2, see What's New in DFS Replication and DFS Namespaces in Windows Server; for Windows Server 2012, see What's New in DFS Namespaces and DFS Replication in Windows Server 2012 [redirected].

Removed or deprecated functionality

The following features are included in Windows Server 2012 R2 and Windows Server 2012, but they are being phased out, and they likely will be removed from future versions of the Windows Server operating system.

For a complete list of deprecated features in Windows Server 2012, see Features Removed or Deprecated in Windows Server 2012.

For more information about FRS support in Windows Server 2012 and Windows Server 2008 R2, see File Replication Service (FRS) Is Deprecated in Windows Server 2008 R2.

Requirements for running DFS

There are no additional hardware or software requirements for running DFS Management or using DFS Namespaces.

Before you can deploy DFS Replication, you must configure your servers as follows:

• Update the Active Directory Domain Services (AD DS) schema to include Windows Server 2012, Windows Server 2008 R2, Windows Server 2008, or Windows Server 2003 R2 schema additions. (If you install a domain controller running Windows Server 2012 the schema is automatically updated.) You cannot use read-only replicated folders with the Windows Server 2003 R2 or older schema additions.

• Ensure that all servers in a replication group are located in the same forest. You cannot enable replication across servers in different forests.

• Install DFS Replication on all servers that will act as members of a replication group.

• Contact your antivirus software vendor to check that your antivirus software is compatible with DFS Replication.

• Locate any folders that you want to replicate on volumes formatted with the NTFS file system. DFS Replication does not support the Resilient File System (ReFS) or the FAT file system. DFS Replication also does not support replicating content stored on Cluster Shared Volumes.

Server Manager information

DFS Namespaces and DFS Replication are a part of the File and Storage Services role. The management tools for DFS (DFS Management, the DFS Namespaces module for Windows PowerShell, and command-line tools) are installed separately as part of the Remote Server Administration Tools.

Installing DFS Namespaces, DFS Replication, and DFS Management

To install the role services and the DFS Management Tools, use one of the following methods.

• To install DFS by using Server Manager

• To install DFS by using Windows PowerShell

To install DFS by using Server Manager

1. Open Server Manager, click Manage, and then click Add Roles and Features. The Add Roles and Features Wizard appears.

2. On the Server Selection page, select the server or virtual hard disk (VHD) of an offline virtual machine on which you want to install DFS.

3. Select the role services and features that you want to install.

   • To install the DFS Namespaces and DFS Replication services, on the Server Roles page, select DFS Namespaces and DFS Replication.

   • To install only the DFS Management Tools, on the Features page, expand Remote Server Administration Tools, Role Administration Tools, expand File Services Tools, and then select DFS Management Tools.

     DFS Management Tools installs the DFS Management snap-in, the DFS Namespaces module for Windows PowerShell, and command-line tools, but it does not install any DFS services on the server.

To install DFS by using Windows PowerShell

• Open a Windows PowerShell session with elevated user rights, and then type the following command, where <name> is the role service or feature that you want to install (see the following table for a list of relevant role service or feature names):

  Install-WindowsFeature <name>
  

  Role service or feature	Name
  DFS Namespaces	FS-DFS-Namespace
  DFS Replication	FS-DFS-Replication
  DFS Management Tools	RSAT-DFS-Mgmt-Con

  For example, to install the Distributed File System Tools portion of the Remote Server Administration Tools feature, type:

  Install-WindowsFeature RSAT-DFS-Mgmt-Con
  

  To install the DFS Namespaces, DFS Replication, and the Distributed File System Tools portions of the Remote Server Administration Tools feature, type:

  Install-WindowsFeature FS-DFS-Namespace, FS-DFS-Replication, RSAT-DFS-Mgmt-Con
  

Interoperability with Azure virtual machines

Using DFS Namespaces and DFS Replication on a virtual machine in Azure has been tested with Windows Server 2012 R2; however, there are some limitations and requirements that you must follow.

For DFS Namespaces:

• You can’t cluster stand-alone namespaces in Azure virtual machines.

• You can host domain-based namespaces in Azure virtual machines, including environments with Azure AD, though a single namespace can’t encompass both on premise namespace servers and namespace servers hosted in Azure VMs, even when using Active Directory Federation Services.

For DFS Replication:

• Using snapshots or saved states to restore a server running DFS Replication for replication of anything other than the SYSVOL folder causes DFS Replication to fail, which requires special database recovery steps. Similarly, don’t export, clone, or copy the virtual machines. For more information, see article 2517913 in the Microsoft Knowledge Base, as well as Safely Virtualizing DFSR.

• When backing up data in a replicated folder hosed in a virtual machine, you must use backup software from within the guest virtual machine.

• DFS Replication requires access to physical or virtualized domain controllers – it can’t communicate directly with Azure AD.

• DFS Replication requires a VPN connection between your on premise replication group members and any members hosted in Azure VMs. You also need to configure the on premise router (such as Forefront Threat Management Gateway) to allow the RPC Endpoint Mapper (port 135) and a randomly assigned port between 49152 and 65535 to pass over the VPN connection. You can use the Set-DfsrMachineConfiguration cmdlet or the Dfsrdiag command line tool to specify a static port instead of the random port. For more information about how to specify a static port for DFS Replication, see Set-DfsrServiceConfiguration. For information about related ports to open for managing Windows Server, see article 832017 in the Microsoft Knowledge Base.

To learn about how to get started with Azure virtual machines, visit the Microsoft Azure web site.

See also

For additional related information, see the following resources.