Chapter 1: Introduction to the Integrated RAID Solution | Benefits and Features SAS2 Integrated RAID Solution User Guide
Page 6 LSI Corporation Confidential | August 2010
1.2 Benefits and Features The LSI Integrated RAID solution has the following benefits and features:
Support for up to 10 di sks per Integrated R AID volume, with o ne or two volumes on
each SAS2 controller. Each controller can support can support 14 volume drives,
including one or two hot spare disks.
Support for two-disk Integrated Mirroring volumes (RAID 1)
Support for online capacity expansion (OCE) for RAID 1 volumes. OCE allows you to
increase the size of a RAID 1 volume by replacing the disk drives with
higher-capacity drives.
Low-cost RAID volume creation, which meets the needs of most internal RAID
installations
Easy installation and configuration
Support for booting from any kind of Integrated RAID volume
Ability to operate without special operating system-specific software
High reliability and data integrity
— Nonvolatile write journaling
— Physical disks in a volume are not visible to the operating system (OS) or to
application software
Low host CPU and PCI bus utilization
Processing power provided by Fusion-MPT architecture
— Sh ared-memory architecture mini mizes external memory requests
— Device hardware and firmware contain the functionality
1.2.1 Host Interface The Integrated RAID host interface uses the message-passing interface, as described in
the Fusion-MPT Message Passing Interface Specification. The Fusion-MPT interface gives
the host OS acce ss to the RA ID volumes a s well as to a dditional non-RAID p hysical dis ks.
1.2.2 Metadata Support The Integrated RAID firmware supports metadata, which describes the logical drive
configuration stored on each member disk of a volume. After initialization, the
firmware queries each member disk to read the metadata and verify the configuration.
The firmware reduces the usable disk space for each member disk when it creates the
the volume, which makes room for the metadata.
1.2.3 SMART Support The Self-Monitoring Analysis and Reporting Technology (SMART) monitors disk drives
for signs of future disk failure and generates an alert if it detects such signs. The
Integrated RAID firmware polls each physical disk in the volume at regular intervals. If
the firmware detects a SMART ASC/ASCQ code on a physical disk in the volume, it
processes the SMART data and stores it in a log. The volume does not support SMART
directly because it is only a logical representation of the physical disks in the volume.
1.2.4 Fusion-MPT Support The Integrated RAID BIOS uses the LSI Fusion-MPT interface to communicate to the
SAS2 controller and firmware. This proc ess includes reading the Fusio n-MPT
configuration to access the parameters that define behavior between the SAS2
controller and the devices that connect to it. The Fusion-MPT drivers for all supported
operating systems implement the Fusion-MPT interface to communicate with the
controller and firmware.