Abstract: Following a loss of power, a storage system switches to a local power supply. The system switches to the local power supply, prevents the receipt of input/output commands and copies the content of cache memory to a local storage device. On detecting resumption of external power, the system charges a local power supply, copies the content of the local storage device to the cache memory and processes the content of the cache memory with respect to at least one storage volume. When the charge stored on the local power supply exceeds the charge required to copy the content of the cache memory to the local storage device by a predetermined amount, the system allows the receipt of input/output commands using a reduced portion of the cache memory. Once the charge stored on the local power supply has reached a predetermined level, the system allows the receipt of input/output commands using all cache memory.

Abstract: A method, system, and computer program product are provided for maintaining a storage device backup consistency group. The method comprises receiving a first I/O command for a first storage device, receiving a second I/O command for a second storage device, identifying a transaction comprising both the first I/O command and the second I/O command, accessing a storage device backup consistency group for the first storage device, determining whether a backup for the second storage device is a member of the storage device backup consistency group, and performing a predefined corrective action if a backup for the second storage device is not a member of the storage device backup consistency group. The predefined corrective action may comprise detecting or creating a backup for the second storage device and then adding the detected or created backup to the storage device backup consistency group, invalidating the second I/O command, and/or issuing a warning.

Abstract: A method of operating a storage system comprises detecting a cut in an external power supply, switching to a local power supply, preventing receipt of input/output commands, copying content of cache memory to a local storage device and marking the content of the cache memory that has been copied to the local storage device. When a resumption of the external power supply is detected, the method continues by charging the local power supply, copying the content of the local storage device to the cache memory, processing the content of the cache memory with respect to at least one storage volume and receiving input/output commands. When detecting a second cut in the external power supply, the system switches to the local power supply, prevents receipt of input/output commands, and copies to the local storage device only the content of the cache memory that is not marked as present.

Abstract: A method of performing a data write on a storage device comprises instructing a device driver for the device to perform a write to the storage device, registering the device driver as a transaction participant with a transaction co-ordinator, executing a flashcopy of the storage device, performing the write on the storage device, and performing a two-phase commit between device driver and transaction co-ordinator. Preferably, the method comprises receiving an instruction to perform a rollback, and reversing the data write according to the flashcopy. In a further refinement, a method of scheduling a flashcopy of a storage device comprises receiving an instruction to perform a flashcopy, ascertaining the current transaction in relation to the device, registering the device driver for the device as a transaction participant in the current transaction with a transaction co-ordinator, receiving a transaction complete indication from the co-ordinator, and executing the flashcopy for the device.

Abstract: A method and system are provided for storage area network configuration across redundant fabrics. The method includes defining (501) a set of redundant fabrics (151, 152), wherein a fabric (151, 152) is a network between devices (111-114, 121-122) of a storage area network (150). A first fabric (151) communicates (502) with the other fabrics (152) in a set of redundant fabrics to send configuration information. Each redundant fabric (152) examines the first fabric's (151) configuration information for devices (111-114, 121-122) to which the redundant fabric (152) is also connected and resolves ports (161, 162) for devices to which the first fabric (151) and the redundant fabric (152) are connected to provide ports (162) on the redundant fabric (152) equivalent to the ports (161) on the first fabric (151).

Abstract: A method of operating a storage system comprises detecting a cut in an external power supply, switching to a local power supply, preventing receipt of input/output commands, copying content of cache memory to a local storage device and marking the content of the cache memory that has been copied to the local storage device. When a resumption of the external power supply is detected, the method continues by charging the local power supply, copying the content of the local storage device to the cache memory, processing the content of the cache memory with respect to at least one storage volume and receiving input/output commands. When detecting a second cut in the external power supply, the system switches to the local power supply, prevents receipt of input/output commands, and copies to the local storage device only the content of the cache memory that is not marked as present.

Abstract: Various method, system, and computer program product embodiments for performing a backup of a source storage volume to a target storage volume are provided. In one exemplary embodiment, a flashcopy of the source storage volume to the target storage volume is initiated. The content of the source storage volume is stored on the target storage volume in a space efficient manner. The space requirement of the stored content on the target storage volume is monitored. The flashcopy is terminated when the space requirement reaches a predetermined level. The stored content on the target storage volume is copied to a backup storage medium. A new flashcopy of the source storage volume is initiated.

Abstract: Embodiments for operation of a storage system following a power loss are provided. The system switches to the local power supply, prevents the receipt of input/output commands and copies the content of cache memory to a local storage device. On detecting resumption of external power, the system charges a local power supply, copies the content of the local storage device to the cache memory and processes the content of the cache memory with respect to at least one storage volume. When the charge stored on the local power supply exceeds the charge required to copy the content of the cache memory to the local storage device by a predetermined amount, the system allows the receipt of input/output commands using a reduced portion of the cache memory. Once the charge stored on the local power supply has reached a predetermined level, the system allows the receipt of input/output commands using all cache memory.

Abstract: A method, system, and computer program product are provided for maintaining a storage device backup consistency group. The method comprises receiving a first I/O command for a first storage device, receiving a second I/O command for a second storage device, identifying a transaction comprising both the first I/O command and the second I/O command, accessing a storage device backup consistency group for the first storage device, determining whether a backup for the second storage device is a member of the storage device backup consistency group, and performing a predefined corrective action if a backup for the second storage device is not a member of the storage device backup consistency group. The predefined corrective action may comprise detecting or creating a backup for the second storage device and then adding the detected or created backup to the storage device backup consistency group, invalidating the second I/O command, and/or issuing a warning.

Abstract: A mechanism is provided for adapting a network topology, in which the network topology comprises a plurality of points, a plurality of connections, each connection connecting a pair of points, and a zoneset comprising a plurality of zones, each zone defining a series of points that are connected. The mechanism performs operations of receiving one or more user inputs, each user input comprising a change to a zone, performing an analysis of the or each user input, to determine one or more consistent universal changes to the zoneset, presenting an output to the user comprising one or more of the determined consistent universal changes to the zoneset, receiving a selection user input selecting a presented consistent universal change to the zoneset, and changing the zoneset according to the selected consistent universal change to the zoneset.

Abstract: The ‘rollback room’ is a demarked area of 3D space in the virtual world—it may be branded by its (trusted) provider. Participants who enter the space take a ‘state checkpoint’ of their virtual world state on entering the area and then become participants in a transaction that is taking place in the rollback room. They can buy, sell, or transfer goods with other parties in the room. They may trust these parties to various degrees but can interact with or try out the new ‘goods’ they have received in the rollback room within the confines of the rollback room as normal.