Introduction to namespaces
Updated: August 22, 2005
Applies To: Windows Server 2003 R2
With DFS Namespaces technology, you can group shared folders located on different servers by transparently connecting them to one or more namespaces. A namespace is a virtual view of shared folders in an organization. When a user views the namespace, the folders appear to reside on a single hard disk. Users can navigate the namespace without needing to know the server names or shared folders hosting the data.
The path to a namespace is similar to a Universal Naming Convention (UNC) path to a shared folder, such as \\Server1\Public\Software\Tools. If you are familiar with UNC paths, you know that in this example, the shared folder Public and its subfolders Software and Tools are all hosted on Server1. Now, assume that you want to give users a single place to locate data, but you want to host data on different servers for availability and performance purposes. To do this, you can deploy a namespace similar to the one shown in the following figure. The elements of this namespace are described after the figure.
Namespace server. A namespace server hosts a namespace. The namespace server can be a member server or domain controller.
Namespace root. The namespace root is the starting point of the namespace. In the previous figure, the name of the root is Public, and the namespace path is \\Contoso\Public. This type of namespace is known as a domain-based namespace because it begins with a domain name (for example, Contoso) and its metadata is stored in the Active Directory® directory service. Although a single namespace server is shown in the previous figure, a domain-based namespace can be hosted on multiple namespace servers to increase the availability of the namespace.
Folder. Folders help build the namespace hierarchy. Folders can optionally have folder targets. When users browse a folder with targets in the namespace, the client computer receives a referral that transparently redirects the client computer to one of the folder targets.
Folder targets. A folder target is a UNC path of a shared folder or another namespace that is associated with a folder in a namespace. In the previous figure, the folder named Tools has two folder targets, one in London and one in New York, and the folder named Training Guides has a single folder target in New York. A user who browses to \\Contoso\Public\Software\Tools is transparently redirected to the shared folder \\LDN-SVR-01\Tools or \\NYC-SVR-01\Tools, depending on which site the user is in.