System and method for ensuring write data integrity in a redundant array data storage system

A method for ensuring the completion and integrity of data modification operations to a redundant data storage array subsystem, comprising the steps of:

• a. providing a first host processor for initiating data modification operations for data records and for generating host check point information about said data modification operations;
• b. providing a second host processor, coupled to the first host processor to receive the host check point information, and for assuming control of initiated data modification operations if the first host processor fails;
• c. providing first and second buffers, coupled to the first and second host processors, to receive and store entire generated data modification operations from the first or second host processor, whereby subsequent failure of either host processor does not affect the received data modification operations;
• d. providing a redundant array of data storage devices for storing data records as indicated by said data modification operations;
• e. providing a first array processor, coupled to the first buffer and to the redundant array of data storage devices, for receiving data modification operations from the first buffer, for controlling the completion of the data modification operations to the redundant array of data storage devices, and for generating array check point information about said data modification operations;
• and
• f. providing a second array processor, coupled to the second buffer, to the redundant array of data storage devices, and to the first array processor, for receiving data modification operations from the second buffer, for receiving the array check point information from the first array processor, and for assuming control of the completion of the data modification operations to the array of data storage devices if the first array processor fails.

A method for ensuring the completion and integrity of data modification operations to a redundant storage array subsystem, comprising the steps of:

• a. initiating data modification operations for data records in a first host processor, and generating host check point information about said data modification operations;
• b. receiving the host check point information in a second host processor, and assuming control by the second host processor of initiated data modification operations if the first host processor fails;
• c. receiving and storing the entire data modification operations in first and second buffers, whereby subsequent failure of either host processor does not affect the received data modification operations;
• d. receiving data modification operations from the first buffer in a first array processor, the first array processor controlling completion of the data modification operations to a redundant array of data storage devices and generating array check point information about said data modification operations;
• and
• e. receiving the data modification operations from the second buffer and the array check point information from the first array processor in a second array processor, the second array processor assuming control of the completion of the data modification operations to the redundant array of data storage devices if the first array processor fails.