Dell POWEREDGE M1000E - Manual (Page 205)

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 8. Chassis With Six-PSU Configuration
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
iDRAC7 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
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