Patent ID: 7263581

Claim:
A system for accessing and verifying validity of data content stored in a cache memory on a disk to be used, after a master disk controller has recovered from a malfunction during which a slave disk controller has temporarily taken over data accessing work executed by the master disk controller in which two independent storage spaces allocated in the cache memory on the disk are available for the master and slave disk controllers, respectively, for data accessing purposes; the system for accessing and verifying the validity of data content stored in the cache memory of disks comprising: a recording area built in the disk for recording records of the disk accessed by the master and slave disk controllers; and a power-on determining program used by the master disk controller to read the accessed records in the recording area upon power-on, to determine whether the accessed records show that the disk was accessed by the master controller; wherein, if the records show that the disk was accessed by the master disk controller, having the master disk controller access the disk with data content stored in a storage space in the cache memory of the master disk controller, and if the records show that the disk was accessed by a slave disk controller, having the master disk controller invalidate the content stored in the storage space in the cache memory of master disk controller after power-on.