An organization has requested storage area network (SAN) disks for a new project. What Redundant Array of Independent Disks (RAID) level provides the BEST redundancy and fault tolerance?
Correct Answer: D
RAID level 5 provides the best redundancy and fault tolerance for SAN disks. RAID level 5 is a type of RAID configuration that uses striping with parity. Striping means that the data is divided into blocks and distributed across multiple disks, which improves the performance and capacity of the disk array. Parity means that an extra block of data is calculated and stored on one of the disks, which provides redundancy and fault tolerance in case of a disk failure. RAID level 5 can tolerate the failure of one disk, and can rebuild the lost data from the parity block. RAID level 5 also offers a good balance between performance and reliability, as it does not sacrifice too much disk space or speed for redundancy . References: [CISSP CBK, Fifth Edition, Chapter 4, page 366]; [CISSP Practice Exam - FREE 20 Questions and Answers, Question 18].