IBM System Storage DS3000, Руководство по программированию

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Parameter Description
isnsRegistration
The means of listing the iSCSI target on the iSNS
server. Set the parameter to TRUE to list it.
Notes
When you use this command, you can specify one or more of the optional parameters.
Auto Support Data
When enabled, the
set storageSubsystem autoSupportConfig
command causes all configuration and state
information for the storage subsystem to be returned each time a critical Major Event Log (MEL) event is
detected. The configuration and state information is returned in the form of an object graph. The object
graph contains all relevant logical and physical objects and their associated state information for the
storage subsystem.
The
set storageSubsystem autoSupportConfig
command collects configuration and state information in
this way:
v
Automatic collection of the configuration and state information occurs every 72 hours. The
configuration and state information is saved to the storage subsystem zip archive file. The archive file
has a time stamp that is used to manage the archive files.
v
Two storage subsystem zip archive files are maintained for each storage subsystem. The zip archive
files are kept on a disk drive. After the 72-hour time period is exceeded, the oldest archive file is
always overwritten during the new cycle.
v
After you enable automatic collection of the configuration and state information using this command,
an initial collection of information starts. Collecting information after the you issue the command
makes sure that one archive file is available and starts the time stamp cycle.
You can run the
set storageSubsystem autoSupportConfig
command on more than one storage
subsystem.
Cache Block Size
When you define cache block sizes, use the 4-KB cache block size for storage subsystems that require I/O
streams that are typically small and random. Use the 8-KB cache block size when the majority of your
I/O streams are larger than 4 KB but smaller than 8 KB. Use the 16-KB cache block size or the 32-KB
cache block size for storage subsystems that require large data transfer, sequential, or high-bandwidth
applications.
This parameter defines the supported cache block size for all of the logical drives in the storage
subsystem. Not all controller types support all cache block sizes. For redundant configurations, this
parameter includes all of the logical drives that are owned by both controllers within the storage
subsystem.
Cache Flush Start and Cache Flush Stop
When you define values to start a cache flush, a value that is too low increases the chance that data
needed for a host read is not in the cache. A low value also increases the number of disk drive writes that
are necessary to maintain the cache level, which increases system overhead and decreases performance.
When setting storage subsystem cache settings, the value of
cacheFlushStart
must be greater than or
equal to the value of
cacheFlushStop
. For example, if the value of
cacheFlushStart
is set to 80, set the
value of
cacheFlushStop
within the range of
0
to
80
.
Chapter 3. Script Commands
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