HP EliteBook 2170p Notebook PC - Manual (Page 6)

2 RAID technology overview
This chapter defines the terms used in this guide and describes the RAID technologies supported by
select HP Business computers.
RAID terminology
Some of the terms in the following table have a broader meaning, but they are defined in relation to
the RAID implementation described in this guide.
Term Definition
Fault tolerance The ability of the computer to continue to operate if one drive fails. Fault tolerance is
often used interchangeably with reliability, but the two terms are different.
HDD One physical hard disk drive in the RAID array.
Option ROM A software module inside the system's BIOS that provides extended support for a
particular piece of hardware. The RAID option ROM provides boot support for RAID
volumes as well as a user interface for managing and configuring the system's RAID
volumes.
Primary drive The main internal hard drive in the computer.
RAID array The physical drives that appear as one logical drive to the operating system.
RAID migration The change of data from a non-RAID to RAID configuration. “RAID level migration,” or
the change of data from one RAID level to another, is not supported.
RAID volume A fixed amount of space across a RAID array that appears as a single hard drive to the
operating system.
Recovery drive The hard drive that is the designated mirror (copy of the primary) drive in a RAID 1 and
Recovery volume.
Reliability The likelihood—over a period of time—that a hard drive can be expected to operate
without failure, also known as mean time before failure (MTBF).
Stripe The set of data on a single hard drive in a RAID volume.
Striping The distribution of data over multiple disk drives to improve read/write performance.
SSD (solid-state drive) A solid-state drive is a flash-based or DRAM-based hard drive with no rotating media.
SED (self-encrypting drive) A self-encrypting drive is a hard drive that uses hardware encryption to protect the data
on the drive.
mSATA module An mSATA module is a flash-memory module with an mSATA connector.
RAID modes supported
The RAID modes supported by HP Business computers include RAID 0, RAID 1, RAID 5, and
Flexible data protection (Recovery) as described below. RAID modes 0, 1, and Recovery require two
SATA hard drives. RAID mode 5 requires three SATA hard drives. This can be accomplished by
inserting a third SATA hard drive into the upgrade bay of specially-equipped computers. RAID 10 is
not supported.
2 Chapter 2 RAID technology overview