Data protection method wherein data protection code is stored together with parity

A method for storing data on a disk drive and checking the validity of data read from such disk drive, comprising:

• transmitting the data from a source thereof for storage in the disk drive and transmitting a Cyclic Redundancy Code (CRC) together with parity associated with such data for storage in a different disk drive:
• retrieving the data stored on the disk drive;
• determining a CRC associated with the retrieved data;
• and
• comparing the determined CRC with the CRC stored in a second disk drive.

A method for storing data on a disk drive and checking the validity of data read from such disk drive, comprising:

• transmitting the data from a source thereof for storage in the disk drive through a first transmission path and transmitting a Cyclic Redundancy Code (CRC) together with parity associated with such data for storage in a storage medium through a second path separate from the disk drive;
• retrieving the data stored on the disk drive;
• determining a CRC associated with the retrieved data;
• and
• comparing the determined CRC with the CRC stored in the storage medium.

A method for storing a plurality of blocks of data on a corresponding one of a plurality of disk and checking the validity of plurality of blocks of data read from such disk drives, comprising:

• transmitting the blocks of data from a source thereof for storage in the disk drives through a plurality of different transmission paths and transmitting Cyclic Redundancy Codes (-CRCs) together with parity associated with each one of the blocks of data for storage in a storage medium through a path separate the plurality of different transmission paths;
• retrieving the blocks of data stored in the disk drives;
• determining CRCs associated with the blocks of retrieved data;
• and
• comparing the determined CRCs with the CRCs stored on the storage medium.

A method for storing a stripe of data comprising a plurality of data blocks, each one of the plurality of blocks of data being stored on a corresponding one of a plurality of disk drives, such stripe of data having a data protection code, each one of the blocks of data having a parity, and checking the validity of the stripe of data read from such plurality of disk drives, comprising:

• transmitting each one of the plurality of blocks of data, together with an associated data protection code, from a source of such blocks of data for storage in a corresponding one of the plurality of disk drives through a corresponding one of a plurality of different data directors, each one of the data directors writing the block of data transmitted thereto into the corresponding one of the plurality of disk drives;
• transmitting a parity associated with the plurality of blocks of data and a data protection code associated with each one of the blocks of data in the source for storage in a separate storage medium through a parity director separate from the plurality of data directors;
• retrieving each one of the plurality of blocks of data stored in each one of the plurality of disk drives for the corresponding one of the plurality of data directors;
• determining from each one of the plurality of data directors a data protection code associated with each one of the retrieved blocks of data;
• comparing the determined data protection codes with the data protection codes stored in the separate storage medium;
• and
• determining from such comparison, whether to rebuild the stripe of data.

A method for storing a stripe of data comprising a plurality of data blocks, each one of the plurality of blocks of data being stored on a corresponding one of a plurality of disk drives, such stripe of data having a data protection code, each one of the blocks of data having a parity, and checking the validity of the stripe of data read from such plurality of disk drives, comprising:

• transmitting each one of the plurality of blocks of data from a source of such blocks of data for storage in a corresponding one of the plurality of disk drives through a corresponding one of a plurality of different data directors, each one of the data directors writing the blocks of data transmitted thereto into the corresponding one of the plurality of disk drives;
• transmitting parity associated with the plurality of blocks of data and a data protection code associated with each one of the blocks of data in the source for storage in a separate storage medium through a parity director separate from the plurality of data directors;
• retrieving each one of the plurality of blocks of data stored in each one of the plurality of disk drives for the corresponding one of the plurality of data directors;
• determining from each one of the plurality of data directors a data protection code associated with each one of the retrieved blocks of data;
• comparing determined data protection codes with the data protection codes stored in the separate storage medium;
• and
• determining from such comparison, whether to rebuild the stripe of data.