IBM DS8900F, Introduction And Planning Manual

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Ethernet switches
The Ethernet switches provide internal communication between the management consoles and the
processor nodes. Two redundant Ethernet switches are provided.
Power
Intelligent rack PDUs (iPDUs) supply power to the storage system, and backup power modules (BPMs)
provide power to the non-volatile dual in-line memory module (NVDIMM) when electrical power is
removed.
Note: iPDUs are included with models 994, 996, and E96. The Rack Mounted model 993 standard 19-
inch wide rack installation (feature code 0939) supports an optional iPDU.
iPDUs provide several benefits.
• IBM Active Energy Manager(AEM) support
• IBM Power Line Disturbance (PLD) compliance up to 20 milliseconds
• Individual outlet monitoring and control
• Firmware updates
• Circuit breaker protection
• Worldwide voltage/power connector support
BPMs retain NVDIMM data when electrical power is removed, either from an unexpected power loss, or
from a normal system shutdown. This improves data security, reliability, and recovery time.
Functional overview
The following list provides an overview of some of the features that are associated with DS8900F.
Note: Some storage system functions are not available or are not supported in all environments. See the
IBM System Storage Interoperation Center (SSIC) website (www.ibm.com/systems/support/storage/
config/ssic) for the most current information on supported hosts, operating systems, adapters, and
switches.
Nondisruptive and disruptive activities
DS8900F supports hardware redundancy. It is designed to support nondisruptive changes: hardware
upgrades, repair, and licensed function upgrades. In addition, logical configuration changes can be
made nondisruptively. For example:
• The flexibility and modularity means that expansion frames can be added and usable storage
capacity can be increased within a frame without disrupting your applications.
• An increase in license scope is nondisruptive and takes effect immediately. A decrease in license
scope is also nondisruptive but does not take effect until the next IML.
• Easy Tier helps keep performance optimized by periodically redistributing data to help eliminate
drive hot spots that can degrade performance. This function helps balance I/O activity across the
drives in an existing drive tier. It can also automatically redistribute some data to new empty drives
added to a tier to help improve performance by taking advantage of the new resources. Easy Tier
does this I/O activity rebalancing automatically without disrupting access to your data.
The following examples include activities that are disruptive:
• The removal of an expansion frame from the base frame.
Energy reporting
You can use DS8900F to display the following energy measurements through the DS CLI:
• Average inlet temperature in Celsius
• Total data transfer rate in MB/s
• Timestamp of the last update for values
Chapter 1. Overview 9