<div class="content" name="Introduction" uuid="e9262950-d03b-48a5-bbc5-cbb3da6299e4"><p>The Distributed File System: Replication (DFS-R) Protocol is
a <a href="81169399-de63-4f92-8da0-91bd31e3c24c#gt_8a7f6700-8311-45bc-af10-82e10accd331" data-linktype="relative-path">remote procedure call
(RPC)</a> that replicates files between servers. <a href="81169399-de63-4f92-8da0-91bd31e3c24c#gt_8f3c866a-07d2-4921-98ba-f5d376bfdba5" data-linktype="relative-path">DFS-R</a> enables creation of
multimaster optimistic file replication systems. It is multimaster, because
files can be changed by any member that participates in replicating shared
files. It is optimistic, because files can be updated without any prior
consensus or serialization. Therefore, files can be changed by any member
without requiring the member to prevent other members from changing the files.</p><p>DFS-R is designed to replicate files, attributes, and file
metadata. DFS-R is intended to interoperate with the user-level <a href="81169399-de63-4f92-8da0-91bd31e3c24c#gt_528b06a4-e67c-43b3-a02d-8738858a691d" data-linktype="relative-path">file system</a> semantics:
Files are replicated when the applications that modify them close the files.
File replication is designed to be performed asynchronously, such that updates
made on one member are processed at the rate at which the receiving machine is
able to receive the updates, without any real-time restrictions on when the
changes must be propagated. DFS-R allows user-level file system operations to
continue independent of protocol operations.</p><p>Sections 1.5, 1.8, 1.9, 2, and 3 of this specification are
normative. All other sections and examples in this specification are
informative.</p></div>