IBM DCS3860, Инструкция по установке, использованию и обслуживанию

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Cache memory
The controller has a cache active LED that indicates the current status of the cache.
The LED is lit when there is data in the cache, and it is off when there is no data
in the cache.
If caching is enabled and the cache active LED is not lit during I/O, it indicates
one of the following conditions:
v
The cache memory from either controller A or controller B has failed.
v The cache sizes in controller A and controller B are not the same.
v
The battery has failed.
Note: Always use the Storage Manager client to check the cache memory settings
before you assume that a hardware device has failed.
See“Controller LEDs” on page 62 for the location of the cache active LED on a
controller.
Controller cache battery
The backup battery unit provides power to back up the cache memory of each
controller onto flash drives in the event of a power failure. Each battery unit
contains a sealed, rechargeable SMART lithium ion battery.
CAUTION:
The battery is a lithium ion battery. To avoid possible explosion, do not burn.
Exchange only with the IBM-approved part. Recycle or discard the battery as
instructed by local regulations. In the United States, IBM has a process for the
collection of this battery. For information, call 1-800-426-4333. Have the IBM part
number for the battery unit available when you call. (C007)
Replace the battery units in the DCS3860 storage system if they are identified as
failing by the Subsystem Management window, or when the battery fault LEDs are
lit. See “Controller LEDs” on page 62 for the location of the battery fault LED.
Replace only the battery unit that is indicated as failed by the LEDs or in the
Subsystem Management window. In a dual controller configuration, you do not
have to replace both battery units when the Battery fault LEDs indicate that only
one battery unit has failed. Each controller has a green Battery charging LED that
indicates the status of the battery unit.
v
The LED is on when the battery is fully charged.
v The LED flashes when the battery is charging or performing a self-test.
v
The LED is off when the battery or the battery charger has failed or is missing.
Cache battery learn cycle
The battery performs a learn cycle the first time the storage system is turned on,
and again every eight weeks thereafter, to assess the charge capacity of the battery.
If the battery fails the learn cycle or takes too much time to reach full charge, the
Battery charging LED turns off, the Battery fault LED turns on and the Storage
Manager identifies the battery as failed.
Chapter 4. Operating the DCS3860 storage system and EXP3800 expansion enclosure
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