Sun Microsystems StorEdge 3000 Series, Руководство по лучшим практикам

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2 Sun StorEdge 3000 Family Best Practices Manual • March 2007
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Logical drives
The best practice for creating logical drives is to add them evenly across the
primary and secondary controllers. With at least one logical drive assigned to
each controller, both controllers are active. This configuration is known as an
active-active controller configuration and allows maximum use of a dual-
controller array's resources.
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Power redundancy
To ensure power redundancy, connect the two power modules to two separate
circuits, such as one commercial circuit and one UPS.
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FC cabling to both controllers
When attaching FC cables for LUNs configured with redundant paths, make sure
one cable is connected to a channel on the upper controller and the other cable is
connected to a different channel on the lower controller. Then, if multipathing
software is configured on the host, a controller can be hot-swapped in the event of
failure without losing access to the LUN.
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Cache optimization
The RAID array’s cache optimization mode determines the cache block size used
by the controller for all logical drives:
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For sequential optimization, the cache block size is 128 Kbyte.
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For random optimization, the cache block size is 32 Kbyte.
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User-configurable stripe size
When you create a logical drive, you can replace the default stripe size with one
that better suits your application.
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For sequential optimization, available stripe size choices include 16 Kbyte, 32
Kbyte, 64 Kbyte, 128 Kbyte, and 256 Kbyte.
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For random optimization, available stripe size choices include 4 Kbyte, 8
Kbyte, 16 Kbyte, 32 Kbyte, 64 Kbyte, 128 Kbyte, and 256 Kbyte.
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Cable to expansion units so there is no single point of failure
Representative sample cabling diagrams are presented in this document for a
number of expansion unit configurations.
Additional RAS Features You Can Use With FC
and SATA Arrays
Even with all the Sun StorEdge 3000 Family’s built-in RAS features and the best
practices described in this document, single points of failure can still occur. For
instance, some rare hardware failures—a midplane or bus failure, for
instance—could conceivably disable both controllers of an active-active