Users Guide

• Reset System (warm boot)
• Power Cycle System (cold boot)
3. Click Apply. For more information, see the iDRAC Online Help.
Executing power control operations using RACADM
To perform power actions, use the serveraction command.
For more information, see the iDRAC RACADM CLI Guide available at www.dell.com/idracmanuals.
Power capping
You can view the power threshold limits that covers the range of AC and DC power consumption that a system under heavy workload
presents to the datacenter. This is a licensed feature.
Power capping in Blade servers
Before a blade system powers up, iDRAC provides the power requirements of the blade system to the chassis manager based on limited
hardware inventory information. If the power consumption increases over time and if the system consumes power near its maximum
allocation, iDRAC may request CMC to increase the maximum potential power, which results in an increase in the power envelope. iDRAC
requests CMC only to increase the power delivery, however, it does not request CMC to reduce the power delivery if the consumption
decreases. If sufficient power is not allocated, the blade system does not power on.
After the system is powered on and initialized, iDRAC calculates a new power requirement based on the actual hardware configuration.
The system stays powered on even if the CMC fails to allocate new power request.
CMC reclaims any unused power from lower priority servers and allocates that power to a higher-priority infrastructure module or a
server.
Viewing and configuring power cap policy
When power cap policy is enabled, it enforces a user-defined power limits on the system. If power-capping is not enabled, the default
hardware power-protection policy is used. This power-protection policy is independent of the user-defined policy. The system
performance is dynamically adjusted to maintain power consumption close to the specified threshold.
Actual power consumption depends on the workload. It may momentarily exceed the threshold until performance adjustments are
completed. For example, consider a system that has a minimum and maximum Potential Power Consumption values of 500 W and 700 W
respectively. You can specify a Power Budget Threshold to reduce consumption to 525 W. When this power budget is configured, the
performance of the system is dynamically adjusted to maintain power consumption of 525 W or less.
If you set a very low power cap or if the ambient temperature is unusually high, power consumption may temporarily exceed the power-
cap while the system is powering up or being reset.
If the power cap value is set lower than the minimum recommended threshold, iDRAC may not be able maintain the requested power cap.
You can specify the value in Watts, BTU/hr, or as a percentage of the recommended maximum power limit.
When setting the power cap threshold in BTU/hr, the conversion to Watts is rounded off to the nearest integer. When the power cap
threshold are read from the system, the Watts to BTU/hr conversion is also rounded off. Because of the rounding off, the actual values
may slightly differ.
Configuring power cap policy using web interface
To view and configure the power policies:
1. In iDRAC Web interface, go to Configuration > Power Management > Power Cap Policy.
The current power policy limit is displayed under the Power Cap Limits section.
2. Select Enable under Power Cap.
3. Under Power Cap Limits section, enter the power limit within recommended range in Watts and BTU/hr or the maximum % of
recommended system limit.
4. Click Apply to apply the values.
Monitoring and managing power
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