Emc Corporation

Dave W Harvey

Michael Paul Wagner

Alan Lee Taylor

Ashish Arun Palekar

Jeffrey Lucovsky

Sriram Nagasubramanian

David M Zeryck

Dean A Herington

Daniel Stack

A method, computer program product, and computing system for receiving, on a first storage processor, a configuration IO request concerning a data array coupled to the first storage processor. The configuration IO request is provided to the data array for execution. A failure indication that the configuration IO request failed to execute is received. In response to receiving the failure indication, a status indicator is determined for a second storage processor coupled to the data array. Whether to reset the first storage processor is determined based, at least in part, upon the status indicator of the second storage processor.

System and method for storage management

Methods and apparatus for generating switch-initiated trespass commands. In an exemplary embodiment, a method includes recognizing that a first switch has a first path to a first target, which is coupled to a logical unit, and a second path to a second target, recognizing that a second switch has a first path to the first target and a second path to the second target, the second target being coupled to the logical unit, and determining whether the first switch should issue a trespass command.

Methods and apparatus for switch-initiated trespass decision making

Methods, systems, and computer program products for preserving atomic writes to disk arrays are disclosed. According to one method, portions of a file are stored in paired locations on a disk array such that a first location of a location pair for a file portion stores scratch data for the file portion and a second portion of the location pair for the file portion stores valid data for the file portion. A bitmap is stored on the disk array. The bitmap has bits indicating whether valid data for each file portion resides in the first or the second location for its respective location pair. A write request to write data to a portion of the file being less than the entire file is received. The bitmap indicates that valid data for the portion of the file to be written to resides in a first memory location of one of the location pairs on the disk array. In response to the write request, the bitmap is copied to memory, the data for the portion of the file requested to be modified is copied from the first location of the one location pair to a second location of the one location pair on the disk array without copying the entire file and modifying the data in the second location based on the data to be written. The bitmap stored in memory is modified to indicate that valid data for the portion of the file resides in the second location of the one location pair and that scratch data for the portion of the file resides in the first location on the disk array. A request to save the modification is received, and, in response to the request to save the modified data, the bitmap stored on the disk array is replaced with the modified bitmap.

Methods, systems, and computer program products for preserving atomic writes using leaves and bitmaps

A computer storage architecture utilizing layered device drivers enables a user to create and install a device driver into a computer. The device driver is installed into the storage unit through a registration process. In order to permit the user to specify a device driver stack for the device driver and specify the relative position of the device driver within the device driver stack, a novel layered device driver registration system that is separate from a operating system device driver registration system is utilized. The layered device driver registration system enables the user to install one or more device drivers and to specify the placement of each device driver by relative to the other device drivers in various device driver stacks. The layered device driver registration system allows a device driver to be dynamically inserted into or removed from a particular device driver stack.

Growing community of inventors

Newton, MA, United States of America

Dave W Harvey