Intel RS2WC040, Hardware User'S Manual

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4 Intel® RAID Controller RS2WC040 Hardware User’s Guide
Redundancy and Error Handling
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In-band SES2.
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Enclosure management support.
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Drive coercion (auto-resizing to match existing disks).
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Support the internal SAS Sideband signal SFF-8485 (SGPIO) interface.
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Auto-detection of failed drives with transparent rebuild. There must be disk activity
(I/O to the drive) for a missing drive to be marked as failed.
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Auto-resume on reboot of initialization or rebuild (must be enabled before virtual
disk creation).
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Smart initialization automatically checks consistency of virtual disks if there are five
or more disks in a RAID 5 array, which optimizes performance by enabling read-
modify-write mode. RAID 5 arrays of only three or four drives use Peer Read mode.
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Smart Technology predicts failures of drives and electronic components.
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Patrol Read checks drives and maps bad sectors.
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Commands are retried at least four times.
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Firmware provides best effort to recognize an error and recover if possible.
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Failures are logged from controller and drive firmware, and SMART monitor.
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Failures are logged in NVRAM, viewable from OS Event Log, Intel
®
RAID Web
Console 2; CIM, LEDs.
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Cache options:
— Write-through: Usually slower but ensures data is on the disk.
— Normal Read: Always reads from the drive after determining exact location of
each read.
— Direct I/O: Reads data directly from disk without checking cache first.
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Access policy:
— RW: allow read and write I/O
— Read Only: allow read I/O only
— Blocked: deny read and write I/O
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Redundancy through:
— Configuration stored in non-volatile RAM and on the drives (COD).
— Hot-swap support.
SAS/SATA Features of the LSISAS2008 Controller
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Provides eight independent phys, each supporting 6 Gb/s and 3 Gb/s SAS data
transfers per PHY, only four phys are utilized by the RAID adapter.
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Supports SSP to enable communication with other SAS devices.