| 摘要 |
An archival storage cluster of preferably symmetric nodes includes a data protection management system that pepodically organizes the then-available nodes into one or more protection sets, with each set comprising a set of n nodes, where "n" refers to a configurable "data protection level" (DPL) At the time of its creation, a given protection set is closed in the sense that each then available node is a member of one, and only one, protection set When an object is to be stored within the archive, the data protection management system stores the object in a given node of a given protection set and then constrains the distribution of copies of that object to other nodes within the given protection set As a consequence, all DPL copies of an object are all stored within the same protection set, and only that protection set |
