Users Guide

Three PSUs No Redundancy Disabled
Grid Redundancy
In Grid Redundancy mode with six PSUs, all six PSUs are active. The three PSUs on the left must connect to one input power grid,
while the three PSUs on the right connect to another power grid.
CAUTION: To avoid a system failure and for Grid Redundancy to work effectively, there must be a balanced set of PSU
properly cabled to separate grids.
If one grid fails, the PSUs on the functioning grid take over without interruption to the servers or infrastructure.
CAUTION: In Grid redundancy mode, you must have balanced sets of PSUs (at least one PSU in each grid). If this
condition is not met, Grid redundancy may not be possible.
Power Supply Redundancy
When power supply redundancy is enabled, a PSU in the chassis is kept as a spare, ensuring that the failure of any one PSU does
not cause the servers or chassis to power-down. Power Supply Redundancy mode requires up to four PSUs. Additional PSUs, if
present, are utilized to improve power efficiency of the system if DPSE is enabled. Subsequent failures after loss of redundancy may
cause the servers in the chassis to power down.
No Redundancy
Power in excess of what is necessary to power the chassis is available, even on a failure, to continue to power the chassis.
CAUTION: The No Redundancy mode uses optimum PSUs when DPSE is enabled for the requirements of the chassis.
Failure of a single PSU could cause servers to lose power and data in this mode.
Power Budgeting For Hardware Modules
CMC offers a power budgeting service that allows you to configure power budget, redundancy, and dynamic power for the chassis.
The power management service enables optimization of power consumption and re-allocation of power to different modules based
on demand.
The following figure illustrates a chassis that contains a six-PSU configuration. The PSUs are numbers 1-6, starting on the left-side
of the enclosure.
Figure 9. Chassis With Six-PSU Configuration
CMC maintains a power budget for the enclosure that reserves the necessary wattage for all installed servers and components.
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