Abstract: A storage system maintains consistency of the stored contents between volumes even when a plurality of remote copying operations are executed asynchronously. A plurality of primary storage control devices and a plurality of secondary storage control devices are connected by a plurality of paths, and remote copying is performed asynchronously between respective first volumes and second volumes. Write data transferred from the primary storage control device to the secondary storage control device is held in a write data storage portion. Update order information, including write times and sequential numbers, is managed by update order information management portions. An update control portion collects update order information from each update order information management portion, determines the time at which update of each second volume is possible, and notifies each-update portion. By this means, the stored contents of each second volume can be updated up to the time at which update is possible.

Abstract: Even when a host does not give a write time to write data, consistency can be kept among data stored in secondary storage systems. The present system has plural primary storage systems each having a source volume and plural secondary storage systems each having a target volume. Once data is received from a host, each of the plural storage systems creates write-data management information having sequential numbers and reference information and sends, to one of the primary storage systems, the data, sequential number and reference information. Each of the secondary storage systems records reference information corresponding to the larges sequential number among serial sequential numbers and stores, in a target volume in an order of sequential numbers, data corresponding to reference information having a value smaller than the reference information based on the smallest value reference information among reference information recorded in each of the plural secondary storage systems.

Abstract: In a system in which data employed by a computer is stored in a storage system, the storage system transfers this data to another storage system and a copy of the data is maintained in the other storage system. The consistency of the copy is maintained even when data is written, to the storage system by a computer, without having a write time applied. A source storage system, when a write time is applied to a write request, records the write time and applies this write time to the received write data and, when no write time is applied, applies the recorded write time to the received write data and transfers the write data with this write time applied thereto, to a target storage system. The target storage system stores the write data in a logical volume in the target storage system in accordance with the write time.

Abstract: An information system including: a first and second storage apparatus including a first and second volume; a failure detection storage apparatus including a third volume; wherein, for backup purposes, the first and second volumes form a remote copy pair, and, for I/O request purposes, are recognized as a single volume labeled with a same volume identifier, but accessible by alternative access paths designated with differing priorities; wherein, if one apparatus detects a failure in the other or a connection failure, the apparatus detecting the failure stores, in the third volume, a failure information flag showing failure; wherein, upon receiving the I/O request through the second access path, the second storage apparatus determines whether the failure information flag is stored in the third volume, and sends an error reply of the I/O request to the host computer if the failure information flag is stored in the third volume.

Abstract: Even when a host does not give a write time to write data, consistency can be kept among data stored in secondary storage systems. The present system has plural primary storage systems each having a source volume and plural secondary storage systems each having a target volume. Once data is received from a host, each of the plural storage systems creates write-data management information having sequential numbers and reference information and sends, to one of the primary storage systems, the data, sequential number and reference information. Each of the secondary storage systems records reference information corresponding to the largest sequential number among serial sequential numbers and stores, in a target volume in an order of sequential numbers, data corresponding to reference information having a value smaller than the reference information based on the smallest value reference information among reference information recorded in each of the plural secondary storage systems.

Abstract: Provided are a method, system, and article of manufacture for controlling a first storage system receiving commands from a first and second managers to create a consistency group with a second storage system. Host writes are received at the first storage system, wherein the first storage system includes a first storage system primary site and a first storage system secondary site. The first storage system sends the host writes from the first storage system primary site to the first storage system secondary site. Host write operations are quiesced at the first storage system in response to a first command from a first manager. Host write operations are resumed at the first storage system in response to receiving a second command from the first manager. The first storage system receives a run command with a marker, wherein the marker indicates a cycle number to control the cycles of the first and second storage systems.

Abstract: There is disclosed a data storage system used in a computer environment where there are plural host computers and plural storage array controllers. When a remote copy is made while assuring the order of writing across plural storage array controllers, one of the host computers gains copy information about all the storage array controllers associated with the remote copy as a representative. The representative one of the storage array controllers collects and stores copy statuses which are individually managed by the storage array controllers for which a remote copy is made. The host computer gains the copy statuses from the representative controller using an instruction to gain the copy statuses.

Abstract: Provided are a method, system, and article of manufacture for managing consistency groups using heterogeneous replication engines replicating data. A common linkage manager issues a prepare to create consistency group command to a first replication manager and a second replication manager, wherein the first and second replication managers issue create consistency group commands to first and second replication engines, respectively, to form a consistency group of data at a first source storage and a second source storage to copy to a first target storage and second target storage, respectively.

Abstract: Availability of an information system including a storage apparatus and a computer is improved. First and second storage apparatuses execute remote copy of copying data written into a first primary volume from the computer to a second primary volume, at least one of the first and second storage apparatuses executes local copy of copying the data written into the first or second primary volume in a self-storage apparatus to the corresponding first or second secondary volume, and the computer switches the destination of a write request of the data from the first storage apparatus to the second storage apparatus in case of a failure occurring in the first storage apparatus.

Abstract: Availability of an information system including a storage apparatus and a computer is improved. First and second storage apparatuses execute remote copy of copying data written into a first primary volume from the computer to a second primary volume, at least one of the first and second storage apparatuses executes local copy of copying the data written into the first or second primary volume in a self-storage apparatus to the corresponding first or second secondary volume, and the computer switches the destination of a write request of the data from the first storage apparatus to the second storage apparatus in case of a failure occurring in the first storage apparatus.

Abstract: First and second storage apparatuses respectively and internally set a remote copy pair for copying data of a first volume to a second volume and associate a third volume with a remote copy pair according to an external command. When an I/O request to the first volume ends in an error, a host computer sends an I/O request directed to the second volume to the second storage apparatus. If the first and the second storage apparatuses detect a failure in the first or the second storage apparatus of the other side or a connection failure between the first and the second storage apparatuses, the first and the second storage apparatuses store in the third volume a failure information flag showing that the failure was detected.

Abstract: There is disclosed a data storage system used in a computer environment where there are plural host computers and plural storage array controllers. When a remote copy is made while assuring the order of writing across plural storage array controllers, one of the host computers gains copy information about all the storage array controllers associated with the remote copy as a representative. The representative one of the storage array controllers collects and stores copy statuses which are individually managed by the storage array controllers for which a remote copy is made. The host computer gains the copy statuses from the representative controller using an instruction to gain the copy statuses.

Abstract: Provided are a backup system and a backup method for backing up data written by a host into a logical volume provided by a storage system, wherein an update location in the logical volume updated by the host is managed, and the storage system is controlled to selectively back up the data written into the update location in the logical volume based on the management result of the update location. It is thereby possible to ensure a fast data read speed in the backup of raw volumes and an easy multiplatform backup, whereby a backup system and a backup method capable of performing backup efficiently are realized.

Abstract: A remote copy system includes a plurality of first storage systems and a plurality of second storage systems. Each first storage system assigns a sequential number to write data received from the host and sends the write data with the sequential number to the second storage system. One of the first storage systems defers the processing of the write request received from the host and instructs each of the first storage systems to create a marker, whereupon each of the first storage systems defers the processing of the write request, creates a marker including a sequential number and having a marker number, and sends the marker to the second storage system. Each of the second storage systems, when receiving a marker from the first storage system, stores the marker number included in the marker.

Abstract: A storage system maintains consistency of the stored contents between volumes even when a plurality of remote copying operations are executed asynchronously. A plurality of primary storage control devices and a plurality of secondary storage control devices are connected by a plurality of paths, and remote copying is performed asynchronously between respective first volumes and second volumes. Write data transferred from the primary storage control device to the secondary storage control device is held in a write data storage portion. Update order information, including write times and sequential numbers, is managed by update order information management portions. An update control portion collects update order information from each update order information management portion, determines the time at which update of each second volume is possible, and notifies each-update portion. By this means, the stored contents of each second volume can be updated up to the time at which update is possible.

Abstract: A storage system including: a controller; and, a plurality of physical storage devices coupled to the controller and constituting a RAID group; wherein the controller provides one or more logical volumes belonging to the RAID group, each of the one or more logical volumes having a plurality of storage areas; one or more virtual volumes, wherein, when receiving a write request to a virtual volume of the one or more virtual volumes, the controller allocates a storage area in a logical volume to the virtual volume; and writes data to the allocated storage area, wherein, when a physical storage device of the plurality of physical storage devices fails, the controller selectively performs a RAID restore process to a storage area allocated to a virtual volume.

Abstract: Availability of an information system including a storage system that performs remote copy between two or more storage apparatuses and a host computer using such storage system is improved. A third storage apparatus including a third volume is coupled to a first storage apparatus, a fourth storage apparatus including a fourth volume is coupled to a second storage apparatus, the first and third storage apparatuses perform remote copy of copying data stored in a first volume to the third volume, the first and second storage apparatuses perform remote copy of copying data stored in the first volume to a second volume, and the third and fourth storage apparatuses perform remote copy of copying data stored in the third volume to the fourth volume.

Abstract: A storage system of this invention maintains consistency of the stored contents between volumes even when a plurality of remote copying operations are executed asynchronously. A plurality of primary storage control devices and a plurality of secondary storage control devices are connected by a plurality of paths, and remote copying is performed asynchronously between respective first volumes and second volumes. Write data transferred from the primary storage control device to the secondary storage control device is held in a write data storage portion. Update order information, including write times and sequential numbers, is managed by update order information management portions. An update control portion collects update order information from each update order information management portion, determines the time at which update of each second volume is possible, and notifies each-update portion.

Abstract: During the normal operation state of a computer system 1000, the data stored in a primary storage system 200P is copied to an intermediate storage system 200I via synchronous copying and the data stored in the intermediate storage system 200I is copied to a secondary storage system 200R via asynchronous copying. During the reverse operation state, however, the data stored in the secondary storage system 200R is copied to the intermediate storage system 200I via asynchronous copying and the data stored in the intermediate storage system 200I is copied to the primary storage system 200P via synchronous copying. In this way, practical remote copying can be carried out in a computer system in which three or more storage devices are installed at different locations and connected serially.

Abstract: Availability of an information system including a storage system that performs remote copy between two or more storage apparatuses and a host computer using such storage system is improved. A third storage apparatus including a third volume is coupled to a first storage apparatus, a fourth storage apparatus including a fourth volume is coupled to a second storage apparatus, the first and third storage apparatuses perform remote copy of copying data stored in a first volume to the third volume, the first and second storage apparatuses perform remote copy of copying data stored in the first volume to a second volume, and the third and fourth storage apparatuses perform remote copy of copying data stored in the third volume to the fourth volume.