The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 2005
Filed:
Jun. 30, 2000
Paul M. Bober, Lexington, MA (US);
Uresh Vahalia, Waban, MA (US);
Aju John, Northborough, MA (US);
Jeffrey L. Alexander, Watertown, MA (US);
Uday K. Gupta, Westford, MA (US);
Paul M. Bober, Lexington, MA (US);
Uresh Vahalia, Waban, MA (US);
Aju John, Northborough, MA (US);
Jeffrey L. Alexander, Watertown, MA (US);
Uday K. Gupta, Westford, MA (US);
EMC Corporation, Hopkinton, MA (US);
Abstract
A file system is migrated from a source file server to a target file server in a data network while permitting clients to have concurrent read/write access to the file system. The target file server issues directory read requests and file read requests to the source file server in accordance with a network file access protocol to transfer the file system from the source file server to the target file server. Concurrent with the transfer of the file system from the source file server to the target file server, the target file server responds to client read/write requests for access to the file system. In a preferred embodiment, the target file server maintains a hierarchy of on-line nodes off-line nodes. The online nodes represent file system objects that have been completely migrated, and the offline nodes representing file system objects that have not been completely migrated. The target file server executes a background process that walks through the hierarchy in order to migrate the objects of the offline nodes. When an object has been completely migrated, the target file server changes the offline node for the object to an online node for the object.