Protocol dialects of NT LM 0.12 and later support distributed filesystem operations. The distributed filesystem gives a way for this protocol to use a single consistent file naming scheme which may span a collection of different servers and shares. The distributed filesystem model employed is a referral - based model. This protocol specifies the manner in which clients receive referrals.
The client can set a flag in the request SMB header indicating that the client wants the server to resolve this SMB's paths within the DFS known to the server. The server attempts to resolve the requested name to a file contained within the local directory tree indicated by the TID of the request and proceeds normally. If the request pathname resolves to a file on a different system, the server returns the following error:
STATUS_DFS_PATH_NOT_COVERED - the server does not support the part of the DFS namespace needed to resolved the pathname in the request. The client should request a referral from this server for further information.
A client asks for a referral with the TRANS2_DFS_GET_REFERRAL request containing the DFS pathname of interest. The response from the server indicates how the client should proceed.
The method by which the topological knowledge of the DFS is stored and maintained by the servers is not specified by this protocol.