Patent ID: 8769197

Claim:
A storage system comprising: a plurality of disk units adapted to store data at respective ranges of logical block addresses (LBAs), the LBAs constituting an entire address space, and a storage control grid operatively connected to the plurality of disk units and comprising a plurality of at least three data servers; wherein each LBA in the entire address space is assigned to at least two data servers among the plurality of at least three data servers: a primary data server configured to have a primary responsibility for handling requests corresponding to said LBA, and a secondary data server configured to have a secondary responsibility for handling requests corresponding to said LBA and to take over the primary responsibility for handling requests corresponding to said LBA if the primary data server fails; and wherein each data server is further configured, in response to a request corresponding to a certain LBA range under its primary responsibility, to identify a data server configured as a secondary data server with regard to the certain LBA range, to generate a primary cache object, and to enable generating a redundancy cache object corresponding to the primary cache object only at the identified secondary data server, the redundancy cache object to be used by the identified secondary data server, when taking the primary responsibility over the certain LBA range, for permanently storing respective data and/or metadata related to the certain LBA range.