Protecting Data against Consecutive Disk Failures in RAID-5

Abstract

In this letter we present a reorganization method to protect against data loss when one or two disks fail in a RAID level 5. The main advantage of the proposed method is that it is robust against a second failure if a first failed disk has not been replaced yet. Our proposal is motivated by the fact that new disks have a high possibility to fail during their first year of operation and during this period there is enough free space to rebuild the lost data in the failed disk and store it by a reorganization in the remaining disks.