METHODS AND APPARATUS FOR MANAGING ERROR CODES FOR STORAGE SYSTEMS COUPLED WITH EXTERNAL STORAGE SYSTEMS

摘要

A system comprising a plurality of storage systems, which uses storage devices of multiple levels of reliability. The reliability as a whole system is increased by keeping the error code for the relatively low reliability storage disks in the relatively high reliability storage system. The error code is calculated using hash functions and the value is used to compare with the hash value of the data read from the relatively low reliability storage disks.

主权项

1. A system comprising:
a first storage system including: a first port to receive I/O operations from host computers; a first storage controller including a first processor and first memory; and a plurality of first storage devices, which stores data received from said host computers, and a second storage system including: a second port to receive I/O operations from said host computers via said first storage controller; a second storage controller including a second processor and a second memory; and a plurality of second storage devices, which stores data received from said host computers, wherein error check codes corresponding to data stored in said plurality of second storage devices are stored in said first storage system.