Patent ID: 9529821
Filing Date: 2016-12-27
CPC Classification: G06F

Claim Text:
1. A method of coordinated file access using NFS (Network File System) protocol for metadata and I/O to a clustered file system's shared disk storage subsystem by using a shared-lock architecture, each active file server in the clustered file system having equivalent access to clustered file system's shared data, comprising: receiving a file access layout request from a client by a first file server in the clustered file system, using a NAS (Network-Attached Storage) protocol, for byte-ranges of a file stored by the file system; generating a file access layout of a set of file servers in the clustered file system for the NFS protocol to use and byte ranges of the file that particular individual file servers of the clustered file system among the set to use for servicing an I/O request for the file, wherein the generated file access layout functions as a shared-lock for the shared-lock architecture; sending the generated file access layout to the client; receiving from the client, an initial I/O request to byte-ranges of the file; requesting coordinated access to the file from a file system byte-range coordinator that coordinates distributed file system access to byte ranges of files by the file servers in the clustered file system; validating that: no file servers in said the clustered file system have conflicting access to the file, byte ranges for the I/O requested are consistent with the generated file access layout, and the first file server is the correct file server for byte ranges of the requested I/O based on the generated file access layout; and if validated, then granting the first file server coordinated file access to the requested byte-ranges of the file and any subsequent I/O requests that are validated with the generated file access layout can be used by the file servers in the clustered file for coordinated access.