Novell, Inc.

Oracle International Corporation

Emc Corporation

Sandisk Technologies Inc.

Ranjan Gupta

Robert A Wipfel

Kattiganehalli Y Srinivasan

Scott Alan Isaacson

Bart Van Assche

Clyde R Griffin

Techniques are disclosed relating to storage device failover. In one embodiment, a plurality of storage devices are represented as cluster resources to a cluster resource manager that manages cluster resources on a plurality of cluster nodes. An indication may be received that a failover operation is requested with respect to one of the plurality of storage devices. In response to the indication, the cluster resource manager may initiate the failover operation. In some embodiments, the failover operation includes changing a first access state of the storage device and a second access state of another storage device. In such an embodiment, the storage device and the other storage device may be associated with a logical unit number. In some embodiments, the storage device is located within a first of the plurality of cluster nodes; the other storage device is located within a second of the plurality of cluster nodes.

Storage device failover

Methods and apparatus involve booting a computing device from a flash device. The flash device has memory partitions, including a read-only and a read/write partition. The read-only includes an operating system for use by the computing device and defines an initial system state. The read/write is configured to store a delta from the initial system state. Upon booting the computing device subsequent to an initial boot, the delta and the initial system state together define the whole system state. In other features, a write engine from the read-only partition tracks changes to the initial system state and writes some, but not all of the changes back to the read/write partition thereby minimizing a number of writes to the flash memory. In this manner, the speed of the flash memory can be used to quickly boot/reboot a computing device, while avoiding the wear limits associated with writing to flash devices.

Flash memory device having memory partitions and including an embedded general purpose operating system for booting a computing device

A method for detecting and resolving a partition condition in a cluster of computers in a networked environment is described. In one example, the method includes creating a scratch pad area and dividing the scratch pad into slots. Each slot is associated with a node within the cluster. A generation number and a list of known nodes are recorded in each slot when a change of membership occurs in the cluster. The slots are compared to ensure the generation number and the list of known nodes matches in each slot, and the partition condition is resolved by creating a list of surviving nodes and re-allocating appropriate resources to each of the surviving nodes.

Method for detecting and resolving a partition condition in a cluster

Methods and apparatus involve providing computing backup for virtual representations on a physical hardware platform without the attendant overhead of an installed backup agent per each of the virtual representations. Representatively, a hardware platform has a processor and memory upon and a plurality of virtual machines are configured on the processor and memory as guest computing devices by way of scheduling control of a hypervisor layer. A common I/O path between the virtual machines and the hardware platform exists in the hypervisor layer and a single backup agent for the entirety of the virtual machines monitors data flows in the common I/O path. In this way, each virtual machine avoids dedicated backup agents, and their attendant overhead, especially by avoiding backup agents configured uniquely per a guest operating system, a guest file system, etc. Some other features contemplate particular I/O paths, operating systems, hypervisors, domains, and computer program products.

Backup without overhead of installed backup agent

A method and system to detect and resolve a partition condition in a cluster of computers in a networked environment is described. The method can include: creating a scratch pad area accessible by the cluster of computers; dividing the scratch pad into a plurality of slots; recording in the plurality of slots, a generation number and a list of known nodes by each one of the plurality of notes, wherein an identifier is written in the list for each node that is known to a writing node; comparing each slot of the plurality of slots to ensure the generation number and the list of known nodes matches in each slot of the plurality of slots; and resolving the partition condition by creating a list of surviving nodes and re-allocating appropriate resources to each of the surviving nodes.

Growing community of inventors

Salt Lake City, UT, United States of America

Ranjan Gupta