IBM DS8882F, Введение и руководство по планированию

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Contributors to the high degree of availability and reliability include the structure
of the storage unit, the host systems that are supported, and the memory and
speed of the processors.
Storage system structure
The design of the storage system contributes to the high degree of availability. The
primary components that support high availability within the storage unit are the
storage server, the processor complex, and the power control card.
Storage system
The storage unit contains a storage server and one pair of storage
enclosures.
Storage server
The storage server consists of two processor complexes and a pair of
power control cards.
Processor complex
The processor complex controls and manages the storage server functions
in the storage system. The two processor complexes form a redundant pair
such that if either processor complex fails, the remaining processor
complex controls and manages all storage server functions.
Power control card
A redundant pair of power control cards (for model 983, cards are located
in the Management enclosure) coordinate the power management within
the storage unit. The power control cards are attached to the service
processors in each processor complex.
Flash drives
The storage system provides you with a choice of drives.
The following drives are available:
v 2.5-inch Flash Tier 0 drives with FDE
– 400 GB
– 800 GB
– 1.6 TB
– 3.2 TB
v 2.5-inch Flash Tier 1 drives with FDE
– 3.8 TB
v 2.5-inch Flash Tier 2 drives with FDE
– 7.6 TB
Note: Intermix of Flash Tier 0, Flash Tier 1, and Flash Tier 2 drives is not
supported.
Drive maintenance policy
The internal maintenance functions use an Enhanced Sparing process that delays a
service call for drive replacement if there are sufficient spare drives. All drive
repairs are managed according to Enhanced Sparing rules.
A minimum of two spare drives are allocated in a device adapter loop. Internal
maintenance functions continuously monitor and report (by using the call home
feature) to IBM when the number of drives in a spare pool reaches a preset
threshold. This design ensures continuous availability of devices while it protects
data and minimizing any service disruptions.
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DS8882F Introduction and Planning Guide