Dell iDRAC8 Power Capping

• Power Off System

• NMI (Non-Masking Interrupt)

• Graceful Shutdown

• Reset System (warm boot)

• Power Cycle System (cold boot)

3. Click Apply. For more information, see the iDRAC Online Help.

To perform power actions, use the serveraction command. For more information, see the iDRAC8

RACADM Command Line Interface Reference Guide available at dell.com/support/manuals.

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.

Before a blade server powers up, iDRAC provides CMC with its power requirements. It is higher than the

actual power that the blade can consume and is calculated based on limited hardware inventory

information. It may request a smaller power range after the server is powered up based on the actual

power consumed by the server. If the power consumption increases over time and if the server is

consuming power near its maximum allocation, iDRAC may request an increase of the maximum

potential power consumption thus increasing the power envelope. iDRAC only increases its maximum

potential power consumption request to CMC. It does not request for a lesser minimum potential power

if the consumption decreases. iDRAC continues to request for more power if the power consumption

exceeds the power allocated by CMC.

After, the system is powered on and initialized, iDRAC calculates a new power requirement based on the

actual blade configuration. The blade stays powered on even if the CMC fails to allocate new power

request.

CMC reclaims any unused power from lower priority servers and subsequently allocates the reclaimed

power to a higher priority infrastructure module or a server.

If there is not enough power allocated, the blade server does not power on. If the blade has been

allocated enough power, the iDRAC turns on the system power.

When power cap policy is enabled, it enforces user-defined power limits for the system. If not, it uses the

hardware power protection policy that is implemented by default. 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 may be less for light workloads and momentarily may exceed the threshold

until performance adjustments are completed. For example, for a given system configuration, the

Maximum Potential Power Consumption is 700W and the Minimum Potential Power Consumption is

500W. You can specify and enable a Power Budget Threshold to reduce consumption from its current

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