Cabinet Configuration Guidelines
This section contains guidelines for properly placing and connecting the disk shelves.
Cabinet Configuration
For safety reasons, mount the heaviest equipment, typically disk shelves, at the bottom
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of the cabinet. Refer to the appropriate Oracle Safety and Compliance Guide for rack-
mounting guidelines.
To best prepare for cabling controllers to disk shelves, now and in the future, mount
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controllers in the middle of the cabinet.
Do not span disk chains across multiple cabinets.
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Do not remove cabinet panels to run cables between cabinets.
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Load Distribution
To maximize performance, use the maximum number of disk chains supported by the
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controller's SAS HBAs. For example, four SAS HBAs with eight chains and eight disk
shelves will have better performance than two SAS HBAs with four chains and eight disk
shelves.
Balance the number of disk shelves across the disk chains in your system.
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The maximum number of disk shelves supported by each disk chain is six.
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Connect each disk chain to two HBAs if available.
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Do not mix disks with different capacities or rotation speeds within a single disk shelf.
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If SAS-2 and SAS-3 drives are in the same disk chain or same disk shelf, the SAS-3 drives
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operate at SAS-2 speeds.
Cable Lengths
The maximum cable length between DE2-24 disk shelves is two meters.
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The maximum cable length between Sun Disk Shelves is 0.5 meters.
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The maximum cable length between a controller and disk shelves is six meters.
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Cabinet Configuration Guidelines
Installation Prerequisites and Hardware Overviews
15