CLI Guide

Shows the system’s operating mode, also called the cache redundancy mode:
● Independent Cache Performance Mode: For a dual-controller system, controller failover is
disabled and data in a controller’s write-back cache is not mirrored to the partner controller. This
improves write performance at the risk of losing unwritten data if a controller failure occurs while
there is data in controller cache.
● Active-Active ULP: Both controllers are active using ULP (Unified LUN Presentation). Data
for volumes configured to use write-back cache is automatically mirrored between the two
controllers to provide fault tolerance.
● Single Controller: The enclosure contains a single controller.
● Failed Over: Operation has failed over to one controller because its partner is not operational.
The system has lost redundancy.
● Down: Both controllers are not operational.
Controller cache parameters:
Write Back Status
Shows the current, system-wide cache policy as determined by auto-write-through logic. This value
is not settable by users. If an auto-write-through trigger condition (such as a CompactFlash failure)
is met, the cache policy for all volumes changes to write-through, overriding the volume-specific
settings. When the problem is corrected, the cache policy reverts to the value configured for each
individual volume.
● Enabled: Write-back. This is the normal state.
● Disabled: Write-through.
● Not up: The controller is not up.
CompactFlash Status
● Not Installed: The CompactFlash card is not installed.
● Installed: The CompactFlash card is installed.
CompactFlash Health
● OK
● Degraded
● Fault
● N/A
● Unknown
Cache Flush
● Enabled: If the controller loses power, it will automatically write cache data to the CompactFlash
card. Cache flush is normally enabled, but is temporarily disabled during controller shut down.
● Disabled: Cache flush is disabled.
Volume cache parameters:
Serial Number
If a volume is specified, its serial number.
Name
If a volume is specified, its name.
Cache Write Policy
If a volume is specified, its cache write policy:
● write-back: Write-back caching does not wait for data to be completely written to disk before
signaling the host that the write is complete. This is the preferred setting for a fault-tolerant
environment because it improves the performance of write operations and throughput.
● write-through: Write-through caching significantly impacts performance by waiting for data
to be completely written to disk before signaling the host that the write is complete. Use this
setting only when operating in an environment with low or no fault tolerance.
Cache Optimization
If a volume is specified, its cache optimization mode:
Alphabetical list of commands
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