Intel SRCMR, User Manual

Page: 27 / 180

Getting Started 27
Are Hot Fix Drives Needed?
Assume that one of the hard disks of the RAID 5 disk array fails (Hot fix drives are available with
RAID 1, 4, 5, and 10 arrays) The disk array is without redundancy. Time Without Redundancy
(TWR) starts to run. Any unnecessary prolongation of the TWR (the time required to get a
replacement drive, or because you did not immediately recognize the failure) increases the risk of
data loss which will occur should a second drive fail. Therefore, redundancy should be restored as
soon as possible and in an automated manner. Integrating a Hot Fix drive (also referred to as hot
spare) as an immediately available and auto-replacing drive is the most effective way to keep the
TWR as short as possible. Only a hot fix drive can ensure optimal disk array security and constant
data availability.
Using a hot fix drive is not compulsory. If you control the disk array at regular intervals and
immediately replace a defective drive (by shutting down the system or hot-plugging), you can
operate your system without a hot fix drive.