Protecting Data Against Early Disk Failures

Disk drives are known to fail at a higher rate during their first year of operation than during the remaining years of their useful lifetime. The authors propose to use the free space that normally exists on new disks to minimize the risk of data loss during that first year. The technique applies to disk arrays that mirror their data on two disks. Whenever a disk fails, the array will reorganize itself by storing a new copy of the disk that failed on one or more disks that have free space. This will protect the data against any single disk failure until the failed disk gets replaced and the system reverts to its original state.