Users Guide

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 oers a power budgeting service that allows you to congure power budget, redundancy, and dynamic power for the chassis.
The power management service enables optimization of power consumption and re-allocation of power to dierent modules based on
demand.
The following gure illustrates a chassis that contains a six-PSU conguration. The PSUs are numbers 1-6, starting on the left-side of the
enclosure.
Figure 17. Chassis With Six-PSU Conguration
CMC maintains a power budget for the enclosure that reserves the necessary wattage for all installed servers and components.
CMC allocates power to the CMC infrastructure and the servers in the chassis. CMC infrastructure consists of components in the chassis,
such as fans, I/O modules, and iKVM (if present). The chassis may have up to 16 servers that communicate to the chassis through the
iDRAC. For more information, see the iDRAC User’s Guide at support.dell.com/manuals.
iDRAC provides CMC with its power envelope requirements before powering up the server. The power envelope consists of the maximum
and minimum power requirements necessary to keep the server operating. iDRAC’s initial estimate is based on its initial understanding of
components in the server. After operation commences and further components are discovered, iDRAC may increase or decrease its initial
power requirements.
When a server is powered-up in an enclosure, the iDRAC software re-estimates the power requirements and requests a subsequent change
in the power envelope.
CMC grants the requested power to the server, and the allocated wattage is subtracted from the available budget. Once the server is
granted a power request, the server's iDRAC software continuously monitors the actual power consumption. Depending on the actual
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Managing and Monitoring Power