| 摘要 |
The present invention provides methods and an infrastructure for performing repetitive data protection and a corresponding restore of data for block oriented data objects comprising several indexed segments. For implementing the invention, timestamps t<SUB>k </SUB>are set by a timer k. Only the first data modification of a segment is recorded, after a timestamp t<SUB>k </SUB>has been set, by storing the old data contents of said segment together with the segment index j and said timestamp t<SUB>k </SUB>as undo-log block in a first journal j<SUB>0</SUB>, before overwriting said segment with the modified new data. Besides, said undo-log blocks are transmitted to N journals j<SUB>i </SUB>for storing redundant undo-log information, with N>1 and i=0, . . . , N-1. According to the present invention for each journal j<SUB>i </SUB>journal-specific timestamps t<SUB>k/i </SUB>are generated, so that each journal j<SUB>i </SUB>is written for a different set of timestamps t<SUB>k/i</SUB>.
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