Avago Technologies MegaRAID SAS 8204ELP - Manual (Page 24)

1-10 Overview
Copyright © 2007 by LSI Corporation. All rights reserved.
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Patrol read
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No reboot necessary after expansion
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More than 200 Qtags per array
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Hardware clustering support on the board
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User-specified rebuild rate
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32-Kbyte nonvolatile random access memory (NVRAM) for storing
RAID system configuration information; the MegaRAID SAS firmware
is stored in flash ROM for easy upgrade.
1.6.1 SAS Features
The following list describes the SAS features of the RAID controllers:
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Provides eight fully independent PHYs
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Supports 3.0 Gbit/s SAS data transfers per PHY
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Supports SSP to enable communication with other SAS devices
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Supports SMP to communicate topology management information
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Provides a serial, point-to-point, enterprise-level storage interface
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Simplifies cabling between devices
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Provides a scalable interface that supports up to 122 devices through
the use of expanders
Note: The number of devices varies depending on the MegaRAID
product. Check the LSI web site (
http://www.lsi.com ) for
specific details about your product.
•
Supports wide ports consisting of 2, 3, or 4 PHYs within a single
quad port
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Supports narrow ports consisting of a single PHY
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Transfers data using SCSI information units
1.6.2 SAS Array Limitations
This section describes the array limitations of the MegaRAID 1078-based
SAS RAID controllers. These include limitations such as the number of
physical disks supported, the maximum number of disks per controller,
and the maximum number of virtual disks allowed per controller.