Abstract:
If the first storage apparatus is suspended, it is determined which of the update number which the journal recently reflected in the second storage apparatus comprises and the update number which the journal recently reflected in the third storage apparatus comprises is the newer. It is determined, in the newer storage apparatus which is determined to comprise the newer update number, whether one or more differential journals from the journal comprising the update number next to the update number which is not determined to be the newer to the journal comprising the update number determined to be the newer exist or not. If the result of the determination is positive, from the newer storage apparatus to the previous storage apparatus which is not the newer of the second and the third storage apparatuses, one or more differential JNLs are copied. In the previous storage apparatus, one or more differential JNLs are reflected in order of the update numbers, to the data volumes in the previous storage apparatus.
Abstract:
PROBLEM TO BE SOLVED: To store the matching of data stored in a secondary storage system, even if a time stamp is not imparted to write object data which a primary storage system receives. SOLUTION: A single computer is provided with a storage management part. The storage management part regularly or irregularly issues ID, which is next to the previously issued ID to one or more primary storage systems (PDKCs). When a write command is received from one of computers, each PDKC creates journal (JNL) that includes the duplicate (journal data) of write target data and the latest ID from the storage management part, and transfers the journal to a secondary storage system (SDKC). The SDKC stores the received JNL and reflects the JNL until the particular JNL among the non-reflected JNL to the secondary volume. The particular JNL has ID which is the oldest next to the oldest ID among the latest arrival ID in one or more SDKCs. COPYRIGHT: (C)2010,JPO&INPIT
Abstract:
In a remote mirroring system, device, and method, a master storage unit stores information in a log and uses the information from the log to quickly resynchronize slave images following a failure in the master storage unit. Upon receiving a write request from a host, the master storage unit stores a write entry in the log. The write entry includes information that identifies a portion of the slave images that may be unsynchronized from the master image due to the write request. The master storage unit then proceeds to update the master image and the slave images. The log is preserved through the failure, such that the.log is available to the master storage unit upon recovery from the failure. When the master storage unit is operational following the failure, the master storage unit resynchronizes the slave images to the master image by copying those portions of the master image indicated in the log to the slave images.
Abstract:
PROBLEM TO BE SOLVED: To ensure consistency of stored contents between volumes even when a plurality of remote copies are respectively executed asynchronously in the storage system. SOLUTION: A plurality of main storage controllers 1 and a plurality of sub storage controllers 2 are connected by a plurality of paths and the respective asynchronous remote copies are executed between respective first volumes 1A and respective second volumes 2A. Write data D1 transferred from the main storage controller 1 to the sub storage controller 2 are kept in a write data storage part 2B. Update order information D2 including the write time and a sequential number is managed in an update order information management part 2D. An update control part 3 gathers the update order information D2 from the respective update order information management parts 2D, decides the point of time at which the respective second volumes 2A can be updated and notifies respective update parts 2C. Thus, the stored contents of the respective second volumes 2A are respectively updated until the point of time at which update is allowed. COPYRIGHT: (C)2008,JPO&INPIT