Abstract: It is provided a management computer which refers to switching level information including switching patterns to be used at a time of switching the first task to the second application server; sets a level of a degree of safety for each of the switching patterns; refers to a stop time for each first task which is allowed upon switching the first task to the second application server; selects one of the switching patterns having a switching time that is shorter than the stop time of the task requirement information which is set to the first task and having the level of the degree of safety that is highest among the switching patterns of the switching level information; stops the second task of the second application server by the selected one of the switching patterns; and then controls the second application server to provide the first task.

Abstract: High availability computer system and fault correction method. If a fault occurs in the current-system physical device allocated to the current-system virtual device of the virtual server, the virtualization mechanism of the physical server configures, for the standby-system virtual device of the virtual server, the standby-system physical device, as a physical device which is used at a high priority, and the virtualization mechanism distributes the request issued from the standby-system virtual device of another virtual server to a standby-system physical device, but, when such a standby-system physical device does not exist, the virtualization mechanism distributes the request to a standby-system physical device configured for high priority usage.

Abstract: A first server including a local disk and a second server are logically partitioned by virtualization units. The first and second servers each have a storage controller LPAR with a local disk sharing function running thereon. The storage controller LPARs running on the first and second servers communicate with each other. When a disk I/O command issued by the second LPAR running on the second server is transferred to the local disk of the first server, the second LPAR reads data stored in the local disk or writes data thereto. In this way, the local disk is shared.

Abstract: Provided is a computer system that requires only a server administrator for construction thereof arid configuration change thereof.

Abstract: In a computer, a logical partition for calculation in which an OS and an application operate and a logical partition for storage for providing a storage function are constructed. In the logical partition for calculation, a device corresponding to a storage device is provided, while the logical partition for storage provides a volume. A memory space that can be shared by the both logical partitions is prepared, and management information describing a sorting destination or a sorting method of an I/O request issued by an application is provided in the memory. If the logical partition for calculation receives an I/O request from the application, the partition refers to the management information and sorts the I/O request to the storage device or the logical partition for storage. The logical partition for storage processes the received I/O request by the storage function and transmits the result to the storage device.

Abstract: A computer system suited for migration of a virtual server between a plurality of physical servers that do not share a storage apparatus via a network is provided. The present invention is a computer system configured to: couple a plurality of computers together, in each of which a plurality of physical servers and a storage apparatus are directly connected within the same chassis, by directly connecting the storage apparatuses of the plurality of computers: and further have a management computer manage the plurality of computers. When the management computer selects another physical server other than a first physical server in a first computer among the plurality of computers as a migration destination of a virtual server, which operates in the first physical server in the first computer, it judges whether the other physical server exists in the first computer or exists in another computer different from the first computer among the plurality of computers.

Abstract: Provided is a computer system that requires only a server administrator for construction thereof and configuration change thereof.

Abstract: The first application program and/or the second application program send(s) an access request to the second cache management module. The second cache management module receives the access request from the first application program and/or the second application program, and references the second cache management table to identify the storage location of the access-target data conforming to the access request. When access-target data exists in first cache area, the second cache management module sends a data transfer request to the first cache management module storing the access-target data, and where access-target data does not exist in the first cache area, acquires the access-target data from the second storage device. When the access-target data is in first cache area, the first cache management module acquires the access-target data conforming to the data transfer request from the relevant first cache area, and sends access-target data to the second cache management module.

Abstract: When a primary server executing a task fails in a computer system where a plurality of servers are connected to an external disk device via a network and the servers boot an operation system from the external disk device, task processing is taken over from the primary server to a server that is not executing a task in accordance with the following method. The method for taking over a task includes the steps of detecting that the primary server fails; searching the computer system for a server that has the same hardware configuration as that of the primary server and that is not running a task; enabling the server, searched for as a result of the search, to access the external disk device; and booting the server from the external disk device.

Abstract: Occupancy amount of physical resource of a virtual server (VS) is calculated based on maximum physical resource amount indicating performance of a physical server (PS), the occupied virtual resource coefficient indicating relation of physical resource amount used by the VS to the physical resource amount allocated to the VS and the allocated physical resource coefficient indicating relation of the allocated physical resource to the maximum physical resource amount of the PS, and change value of the occupied physical resource amount from a predetermined occupied physical resource amount is calculated based on the calculated occupancy amount and the predetermined occupied physical resource amount.

Abstract: An resource management system example includes node configuration information for managing a hardware configurations of nodes, virtual apparatus management information for managing virtual apparatuses operating in the nodes, and virtual storage configuration condition information for managing configurations of virtual storage apparatuses and hardware resource conditions required to satisfy the configurations of the virtual storage apparatuses in association with each other.

Abstract: A first server stores start administration information identifying a second server into a storage unit which stores an operating system to be started in the second server. The second server makes a decision whether a storage unit which is access set has start administration information identifying the second server stored therein If the storage unit which is access set is judged according to the decision to have start administration information identifying the second server stored therein the second server starts the operating system stored in the storage unit which is access set.

Abstract: Allocation of virtual disk volumes of a size designated by the computer manager to a virtual computer and accessiblity from the virtual computer to the virtual disk voumes without requiring intervention by a hypervisor are to be achieved. In a computer, at least one virtual computer to be in execution on the computer, and a computer system in which the virtual computer has volumes for holding data, a virtualization mechanism has a virtual volume allocating unit and a virtual volume information supplying unit, and the virtual computer has a virtual volume driver for converting positional information on virtual volumes. Additionally, the virtualization mechanism holds the virtual volume information together with defining information for the virtual computer to which the virtual volumes have been allocated.

Abstract: Proposed are a computer system and a performance assurance method capable of stabilizing the I/O performance of a plurality of logical partitions sharing a network path.

Abstract: It is provided a management computer which refers to switching level information including switching patterns to be used at a time of switching the first task to the second application server; sets a level of a degree of safety for each of the switching patterns; refers to a stop time for each first task which is allowed upon switching the first task to the second application server; selects one of the switching patterns having a switching time that is shorter than the stop time of the task requirement information which is set to the first task and having the level of the degree of safety that is highest among the switching patterns of the switching level information; stops the second task of the second application server by the selected one of the switching patterns; and then controls the second application server to provide the first task.

Abstract: In a computer system wherein plural servers are connected with an external disk device via a network, each server incorporates therein a logic partition module for configuring at least one logic partition in the server, and the operating system stored in the logic partition is booted by the boot disk of an external disk device, the failover operation is performed only for the logic partition affected by a failure when the task being executed by a working server is taken over by another server at the time of the failure occurring in the working server.

Abstract: In a network computer system, recovery may be impossible from a fault when the fault occurs in a network switch in a network or a device such as an external disk device. Provided is a computer system that includes a plurality of servers, a plurality of network, a plurality of external disk devices, and a management computer, in which the management computer detects a fault which is occurred, retrieves an application stop server inaccessible to the used disk due to the fault, retrieves the disk for storing the same contents as contents stored in the disk used by the retrieved application stop server and the external disk device including the disk, retrieves an application resuming server capable of accessing the retrieved external disk device, and transmits an instruction to boot by using the retrieved disk to the retrieved application resuming server.

Abstract: There is disclosed a high speed switching method for a disk image delivery system fail-over. A management server sends a disk image of an active server in advance to a standby server. When receiving a report that the active server has failed, the management server judges whether or not it is possible for the standby server to perform the service of the failed active server based on service provision management server information held by the management server and if possible, instructs the standby server to perform the service of the active server. Even if the disk image delivered in advance is different from the disk image of the failed active server, switching of the service to the standby server can be performed more quickly through resetting the setting values of unique information and installing the additional pieces of software on the standby server by the management server than redelivering an appropriate disk image.

Abstract: In a computer system in which a server has, in addition to a disk used for booting, an operation transfer destination disk that has the same content as the boot disk, a method for changing the disk used by the server or another server in the computer system for booting to the operation transfer destination disk is realized by changing the content of the operation transfer destination disk to enable the OS and applications installed in the operation transfer destination disk to be booted from the destination disk and by changing the setting of a boot program of the server to enable booting from the operation transfer destination disk.

Abstract: A first server including a local disk and a second server are logically partitioned by virtualization units. The first and second servers each have a storage controller LPAR with a local disk sharing function running thereon. The storage controller LPARs running on the first and second servers communicate with each other. When a disk I/O command issued by the second LPAR running on the second server is transferred to the local disk of the first server, the second LPAR reads data stored in the local disk or writes data thereto. In this way, the local disk is shared.