Sas Features; Sas Array Limitations - Intel 12Gb/s User Manual

Feature
User-specified rebuild rate (specifying the percentage
of system resources to use from 0 percent to 100
percent)
Nonvolatile random access memory (NVRAM) of 32
KB for storing RAID system configuration information;
the MegaRAID SAS firmware is stored in flash ROM
for easy upgrade.
Full MegaRAID Software Stack
iMR Software Stack

SAS Features

The 12Gb/s Intel
•
They provide four fully independent PHYs or eight fully independent PHYs,
depending on the controller.
•
They support 12 Gb/s, 6Gb/s and 3Gb/s SAS data transfers per PHY.
•
They support SMP to communicate topology-management information.
•
They support SSP to enable communication with other SAS devices.
•
They support STP to enable communication with SATA devices through an
attached expander.
•
They provide a serial, point-to-point, enterprise-level storage interface.
•
They simplify cabling between devices.
•
They provide a scalable interface that supports up to 240 devices through the use of
expanders.
Note: The number of devices varies depending on the Intel
•
They support wide ports that consist of two, three, or four PHYs within a single
quad port.
•
They support narrow ports consisting of a single PHY.
•
They transfer data by using SCSI information units.

SAS Array Limitations

This section describes the array limitations of the 12Gb/s Intel
limitations include the number of drives supported per controller, the maximum number
of drives per controller, and the maximum number of virtual drives allowed per controller.
The following table lists the array limitations for the 12Gb/s Intel
12Gb/s Intel® RAID Controllers User Guide
®
RAID Controllers support the following SAS features:
product. Check the Intel website, http://www.intel.com, for specific details
about your product.
RS3WC080 RS3DC040
Yes Yes
Yes Yes
No Yes
Yes No
RS3DC080
Yes
Yes
Yes
No
®
RAID Controller
®
RAID Controllers. These
®
RAID Controllers.
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