•
POST messages
Smart Array controllers produce diagnostic error messages (POST messages) at reboot. Many POST
messages suggest corrective actions. For more information about POST messages, see the ProLiant
Servers Troubleshooting Guide.
•
HPE Smart Storage Administrator
For information about error messages, see the
ProLiant Servers Troubleshooting Guide
.
•
HPE Smart Storage Administrator Diagnostics Utility CLI
This standalone diagnostic utility provides configuration and error information about array controllers,
storage enclosures, drive cages, logical drives, physical drives, and tape drives. For any supported
SSDs, the utility provides current usage level and remaining expected lifetime. For more information,
see "
Smart Storage Administrator Diagnostics Utility CLI
."
Drive arrays and fault-tolerance methods
Drive arrays
The capacity and performance of a single physical (hard) drive is adequate for home users. However,
business users demand higher storage capacities, higher data transfer rates, and greater protection
against data loss when drives fail.
Connecting extra physical drives (P
n
in the figure) to a system increases the total storage capacity but
has no effect on the efficiency of read/write (R/W) operations. Data can still be transferred to only one
physical drive at a time.
With an array controller installed in the system, the capacity of several physical drives can be combined
into one or more virtual units called
logical drives
(also called
logical volumes
and denoted by L
n
in the
figures in this section). Then, the read/write heads of all the constituent physical drives are active
simultaneously, reducing the total time required for data transfer.
Because the read/write heads are active simultaneously, the same amount of data is written to each drive
during any given time interval. Each unit of data is called a
block
(denoted by B
n
in the figure), and
adjacent blocks form a set of data
stripes
(S
n
) across all the physical drives that comprise the logical
drive.
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Drive arrays and fault-tolerance methods
