Patent ID: 8386834

Claim:
A method comprising: receiving, by a storage system, a notification indicating a failure of a storage device in a cache storage array for caching data; determining whether a number of failures exceeds a fault tolerance level of the cache storage array; and if the number of failures exceeds the fault tolerance level, recovering an address space corresponding to the failed storage device, wherein recovering the address space comprises: replacing the failed storage device with a spare storage device having an identifiable pattern stored thereon; determining whether a file system on the storage system can automatically invalidate cached data blocks on the failed storage device; if the file system cannot automatically invalidate cached data blocks on the failed storage device, setting an indicator for each of a plurality of data blocks on the spare storage device, wherein the indicator indicates that an associated data block has an unrecoverable error, and wherein the associated data block contains the identifiable pattern; and updating a parity calculation for a stripe of data blocks in the storage system, wherein the stripe of data blocks includes a data block on the spare storage device, and wherein the data block on the spare storage device contains the identifiable pattern.