Users Guide

Related links
Power Conservation and Power Budget
Maximum Power Conservation Mode
Server Power Reduction to Maintain Power Budget
110V PSUs AC Operation
Server Performance Over Power Redundancy
Remote Logging
External Power Management
Conguring Power Budget and Redundancy Using CMC Web Interface
Conguring Power Budget and Redundancy Using RACADM
Power Conservation and Power Budget
CMC conserves power when the user-congured maximum power limit is reached. When the demand for power exceeds the user
congured System Input Power Cap, CMC reduces power to servers in reverse-priority order. This allows power for higher priority servers
and other modules in the chassis.
If all or multiple slots in the chassis are congured with the same priority level, CMC decreases power to servers in increasing slot number
order. For example, if the servers in slots 1 and 2 have the same priority level, the power for the server in slot 1 is decreased before that of
the server in slot 2.
NOTE: You can assign a priority level to each server in the chassis assigning a number from 1 through 9 for each server. The
default priority level for all servers is 1. The lower the number, the higher the priority level.
The power budget is limited to a maximum value equal to that of the set of three PSUs that is the weakest. If you attempt to set an AC
power budget value that exceeds the System Input Power Cap value, CMC displays a failure message. The power budget is limited to
16685 Watts.
Maximum Power Conservation Mode
CMC performs maximum power conservation when:
• Maximum conservation mode is enabled
• An automated command line script, issued by a UPS device, enables maximum conservation mode.
In maximum power conservation mode, all servers start functioning at their minimum power levels, and all subsequent server power
allocation requests are denied. In this mode, the performance of powered on servers may be degraded. Additional servers cannot be
powered on, regardless of server priority.
The system is restored to full performance when the maximum conservation mode is cleared.
NOTE
: If the Maximum Power Conversation Mode (MPCM) is enabled on the chassis, all power requests from a blade server are
denied. The blade server is not powered on if there is any action in the iDRAC or blade server requiring the host to start the
power cycle.
Server Power Reduction to Maintain Power Budget
CMC reduces power allocations of lower priority servers when additional power is needed to maintain the system power consumption
within the user-congured System Input Power Cap. For example, Managing and Monitoring Power 297 when a new server is engaged,
CMC may decrease power to low priority servers to allow more power for the new server. If the amount of power is still insucient after
reducing power allocations of the lower priority servers, CMC lowers the performance of servers until sucient power is freed to power
the new server.
Managing and Monitoring Power
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