Asus LSI SAS3442X-R - Manual (Page 18)

2-2 Overview of Integrated Mirroring and Integrated Mirroring Enhanced
Version 1.1 Copyright © 2006, 2007 by LSI Logic Corporation. All rights reserved.
controller can have one or two global hot spare disks available to
automatically replace a failed disk in the IM or IME storage volumes on
the controller. Hot spares make the IM/IME volume even more fault-
tolerant.
Note: You can also configure one IM or IME volume and one
Integrated Striping (IS) volume on the same LSI SAS
controller.
The IM/IME feature uses the same device drivers as the standard LSI
Fusion-MPT based controllers, providing seamless and transparent fault
tolerance. This eliminates the need for complex backup software or
expensive RAID hardware. The IM/IME feature operates independently
from the operating system, in order to conserve system resources. The
BIOS-based configuration utility makes it easy to configure IM and IME
volumes.
2.2 IM and IME Features
IM and IME support the following features:
•
Configurations of one or two IM or IME volumes on the same LSI
SAS controller. IM volumes have two mirrored disks; IME volumes
have three to ten mirrored disks. Two volumes can have up to 12
disks total. (Requires Integrated RAID firmware v1.20.00 or above.)
•
One or two global hot spare disks per controller, to automatically
replace failed disks in IM/IME volumes. (Support for two hot spares
requires Integrated RAID firmware v1.20.00 or above.) The hot
spares are in addition to the 12-disk maximum for two volumes per
SAS controller.
•
Mirrored volumes run in optimal mode or in degraded mode (if one
mirrored disk fails).
•
Hot swap capability.
•
Presents a single virtual drive to the OS for each IM/IME volume.
•
Supports both SAS and SATA disks. The two types of disks cannot
be combined in the same volume. However, an LSI SAS controller
can support one volume with SATA disks and a second volume with
SAS disks.