NetApp Assigned Six Patents

Correcting errors beyond fault tolerant level
of RAID in storage system

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,417,987) developed by Atul Goel, Sunnyvale, CA, and Sunitha Sankar, Cupertino, CA, for a "mechanism for correcting errors beyond the fault tolerant level of a raid array in a storage system."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "Embodiments of the present invention provide novel, reliable and efficient technique for tracking, tolerating and correcting unrecoverable errors (i.e., errors that cannot be recovered by the existing RAID protection schemes) in a RAID array by reducing the need to perform drastic recovery actions, such as a file system consistency check, which typically disrupts client access to the storage system. Advantageously, ability to tolerate and correct errors in the RAID array beyond the fault tolerance level of the underlying RAID technique increases resiliency and availability of the storage system."

The patent application was filed on Dec. 1, 2009 (12/629,032).

N-way parity technique for enabling recovery
from up to N storage device failures

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,402,346) developed by Atul Goel, Foster City, CA, and Peter F. Corbett, Lexington, MA, for an "N-way parity technique for enabling recovery from up to N storage device failures."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "An n-way parity protection technique enables recovery of up to n storage device (e.g., disk) failures in a parity group of a storage array encoded to protect against n-way disk failures. The storage array is created by first configuring the array with m data disks, where m=p-1 and p is a prime number and a row parity disk. n-1 diagonal parity disks are then added to the array. Each diagonal parity set (i.e., diagonal) is associated with a slope that defines the data and row parity blocks of the array that are included in the diagonal. All diagonals having a common slope within a parity group are organized as a diagonal parity class. For each diagonal parity class, a diagonal parity storage disk is provided to store the diagonal parity."

The patent application was filed on Sept. 25, 2009 (12/536,063).

Servicing daemon for live debugging of storage systems

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,402,170) developed by Michael David Harris, Durham, NC, for a "servicing daemon for live debugging of storage systems."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A servicing daemon is described herein for providing servicing of a running computer system (such as a filer). The servicing daemon resides and executes on the OS of the filer and communicates across a network with a debugger that resides and executes on a remote administering computer. A debugging session is performed that complies with a protocol relating to the remote accessing of files. The debugging session provides live servicing of an application executing on the filer without requiring an actual corefile (having copied filer memory data) to be created. Rather, the servicing daemon creates a simulated corefile header that is sent to the debugger, receives requests from the debugger, and maps addresses specified in the requests to filer memory addresses. The servicing daemon then reads and retrieves data directly from filer memory at the determined filer memory addresses and sends the data to the debugger for analysis."

The patent application was filed on Aug. 9, 2011 (13/206,297).

HA network storage system
incorporating non-shared storage
suitable for virtual storage servers

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,412,672) developed by Prashanth Radhakrishnan, and Vaibhav Singh, Bangalore, India, for a "HA network storage system incorporating non-shared storage suitable for use with virtual storage servers."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A technique is disclosed for providing HA capability with a plurality of storage servers, which may be virtual storage servers (VSSs), in a shared-nothing storage environment. The technique uses a proxy mechanism to route requests originating at one storage server to an HA partner storage server, where the proxy is implemented inside a VSS logically below the RAID layer. The technique also involves distributing non-shared storage devices ‘owned’ by a storage server so that existing storage device-based heartbeat and fencing mechanisms can function unmodified for HA VSSs in shared-nothing environments. For example, a third, external host can be used to provide and export its non-shared storage to first and second storage servers, where the first and second storage servers do not own the non-shared storage on their local physical host machine."

The patent application was filed on Sept. 8, 2010 (12/877,890).

Migration of storage object between storage servers
based on ancestry of storage object
in network storage system

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,429,360) developed by Rahul Iyer, Deepak Kenchammana-Hosekote, and Arthur F. Lent, Sunnyvale, CA, for a "method and system for efficient migration of a storage object between storage servers based on an ancestry of the storage object in a network storage system."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "Embodiments of the present invention provide a method and system, in a network storage system, for efficiently migrating a storage object (vdisk) from a first storage server (source) to a second storage server (destination) using data of a related vdisk at the destination. A related vdisk includes an earlier created vdisk (parent) from which the vdisk to be migrated (child) is generated (cloned). By virtue of the cloned relationship, the parent and child have a portion of data blocks in common. When a parent is available at the destination, only the changed data blocks between the parent and child need to be migrated for efficiently constructing the child at the destination."

The patent application was filed on Nov. 13, 2009 (12/618,415).

Deleting file from secure storage served by storage system

NetApp, Inc., Sunnyvale, CA, has been assigned a patent (8,397,083) developed by Robert Jan Sussland, Lawrence Wen-Hao Chang, San Francisco, CA, and Ananthan Subramanian, Menlo Park, CA, for a "system and method for efficiently deleting a file from secure storage served by a storage system."

The abstract of the patent published by the U.S. Patent and Trademark Office states: "A system and method efficiently deletes a file from secure storage, i.e., a cryptainer, served by a storage system. The cryptainer is configured to store a plurality of files, each of which stores an associated file key within a special metadata portion of the file. Notably, special metadata is created by a security appliance coupled to the storage system and attached to each file to thereby create two portions of the file: the special metadata portion and the main, ‘file data’ portion. The security appliance then stores the file key within the specially-created metadata portion of the file. A cryptainer key is associated with the cryptainer. Each file key is used to encrypt the file data portion within its associated file and the cryptainer key is used to encrypt the part of the special metadata portion of each file. To delete the file from the cryptainer, the file key of the file is deleted and the special metadata portions of all other files stored in the cryptainer are re-keyed using a new cryptainer key. Thereafter, the "old" cryptainer key is deleted."

The patent application was filed on Aug. 23, 2006 (11/508,430).