Patent ID: 8078906
Filing Date: 2011-12-13
Classification: G06F

Abstract:
1. A method of operating a storage system comprising a plurality of disk units, and a storage control grid operatively connected to the plurality of disk units and comprising a plurality of data servers, each server comprising cache memory and a non-volatile memory, wherein a first server among said plurality of data servers is configured to have a primary responsibility for handling requests directed to a certain range of logical block addresses (LBAs), and a second server among said plurality of data servers is configured to have a secondary responsibility for handling requests directed to said certain range of LBAs, to overtake the primary responsibility for handling respective requests if the first server fails and to return said primary responsibility to the first server upon its successful reboot; the method comprising: a) continuously obtaining configuration metadata indicative of configuration and/or changes thereof related to said certain data range and saving said configuration metadata and/or derivatives thereof at one or more disk units among said plurality of disk units in accordance with a predefined criterion, b) continuously saving in cache memory of a respective server said configuration metadata and/or derivatives thereof obtained between said savings at disk units, thus giving rise to recent configuration changes (RCC) metadata, c) destaging the recent configuration changes metadata to non-volatile memory of the first server if the first server fails; d) responsive to successful reboot of the first server and until successful overtaking the respective primary responsibility by the first server, sending said-RCC metadata saved in the cache memory of the second server and/or derivatives thereof to the first server.