18.104.22.168 Receiving an SMB2 OPLOCK_BREAK Notification
If the MessageId field of the SMB2 header of the response is 0xFFFFFFFFFFFFFFFF, this MUST be processed as an oplock break indication. Otherwise, the client MUST process it as a response to an oplock break acknowledgment.
If Connection.Dialect is not "2.0.2", the client MUST verify:
If Connection.SupportsFileLeasing is TRUE or Connection.SupportsDirectoryLeasing is TRUE, the client MUST use the StructureSize field in the SMB2 OPLOCK_BREAK notification to differentiate between an oplock break notification and a lease break notification as specified in 2.2.25.