the form \\<SERVER>\<path>\<subpath> Domain-based DFS file share paths are distinguished by using the domain name in place of the server name, in the form \\<DOMAIN.NAME>\<dfsroot>\<path> When a user accesses such a share, either directly or by mapping a drive, their computer will access one of the available servers associated with that share, following rules which can be configured by the network administrator. For example, the default behaviour is that users will access the closest server to them; but this can be overridden to prefer a particular server. If a server fails, the client can select a different server transparently to the user. One major caveat regarding this flexibility is that currently-open files will potentially become unusable, as open files cannot be failed-over. DFS replication Early versions of DFS used Microsoft's File Replication Service (FRS) which provides basic file replication capability between servers. FRS identifies changed or new files, and copies the latest version of the entire file to all servers. Windows Server 2003 R2 introduced "DFS Replication" (DFSR) which improves on FRS by only copying those parts of files which have changed (remote differential compression), by using data compression to reduce network traffic, and by allowing administrators flexible configuration options for limiting network traffic with a customizable schedule. History The server component of Distributed File System was first introduced as an add-on to Windows NT 4.0 Server, called "DFS 4.1", and was later included as a standard component of all editions of Windows 2000 Server. Client-side support is included in Windows NT 4.0 and later versions of Windows. Linux kernels 2.6.14 and later come with an SMB client VFS called "cifs" that supports DFS. On Mac OS X DFS is supported natively in Mac OS X 10.7 ("Lion") onward. Specifications There are a number of specifications that are relevant to DFS, they are available through the Microsoft Open Specifications program: [MS-DFSC]: Distributed File System (DFS): Referral Protocol Specifies the Distributed File System (DFS): Referral Protocol, which enables file system clients to resolve names from a namespace distributed across many servers and geographies into local names on specific file servers. [MS-DFSNM]: Distributed File System (DFS): Namespace Management Protocol Specifies the Distributed File System (DFS): Namespace Management Protocol, which provides an RPC interface for administering DFS configurations. The client is an application that issues method calls on the RPC interface to administer DFS. The server is a DFS service that implements support