User Guide

Intel® Integrated RAID Solution User Guide 5
2 Overview of Integrated RAID
Mirrored Volumes
This chapter provides an overview of the Intel
®
Integrated RAID features that support the
creation of mirrored volumes.
Overview
As a result of the shift towards network-attached storage (NAS), Internet service providers
need a cost-effective, fault-tolerant solution to protect the operating systems on small
form-factor, high-density, rack-mountable servers. The mirroring features of the Intel
®
Integrated RAID Solution provide such protection for the system boot volume, which
safeguards the operating system and other critical information on servers and high-
performance workstations. The Integrated RAID solution supports the following types of
mirrored volumes:
• The Integrated Mirroring solution, which provides features of RAID 1
• The Integrated Mirroring + Striping solution, which provides features of RAID 10
• The Integrated Mirroring Enhanced solution, which provides features of RAID 1
Enhanced (RAID 1E)
These three mirroring solutions provide a robust, high-performance, fault-tolerant
solution to data storage needs at a lower cost than a dedicated RAID controller.
Mirrored volumes contain two disks to ten disks to provide fault-tolerant protection for
critical data. Mirrored volumes also support one or two global hot spare drives, with a
maximum of 14 drives on each Intel SAS-3 controller.
Note: Fourteen drives is the theoretical upper limit for a single Intel SAS-3 controller, although
the controller itself might support fewer than 14 drives. You can also configure one
mirrored volume and one Integrated Striping volume on the same Intel SAS controller.
Each SAS-3 controller can have two global hot spare disks available to automatically
replace a failed disk in the one or two mirrored volumes configured on the controller. The
hot spares make the mirrored volumes even more fault tolerant.