Power management policies
You can set the power management policy to be used for the BladeCenter S system from the advanced management module.
- AC power source redundancy
With this policy, the total allowable power draw is limited to the capacity of two power modules. If you use dual ac power sources, one ac power source can fail without affecting the operation of the blade servers. However, some blade servers may not be able to power on if doing so will exceed the power policy limit.
The policy is intended for use when you have four power modules installed and two separate 220-volt AC power sources.
- AC power source redundancy with blade throttling allowed
This policy is similar to AC power source redundancy. With this policy, the total allowable power draw is limited to the capacity of two power modules. If you use dual ac power sources, one ac power source can fail without affecting the operation of the blade servers.
If power module redundancy is lost, processors on blade servers that are capable of throttling will throttle to reduce the power consumed to less than or equal to the total power. Throttling refers to achieving lower power consumption for a blade by temporarily reducing the CPU throughput. The advanced management module utilizes power management technologies built into certain processors to throttle the blades.NoteNot all blade servers are capable of throttling.The policy is intended for use when you have four power modules installed and two separate 220-volt AC power sources.
- Power module redundancy
With this policy, the total allowable power draw is limited to one less than the number of power modules when more than one power module is present. One power module can fail without affecting blade server operation.
Blade servers will power on only if they can operate without throttling if there is a power module failure. The number of blade servers allowed to power on is determined by the power available from one less than the total number of power modules. If a single power module fails, all the blade servers that are powered on will continue to operate at normal performance levels. If two or more power modules fail, the BladeCenter S chassis could power off.
This policy is intended when you have two to four power modules installed and a single 110-volt or 220-volt AC power source. Each power module is on its own dedicated circuit.
- Power module redundancy with blade throttling allowed
With this policy, the total allowable power draw is limited to one less than the number of power modules when more than one power module is present. One power module can fail without affecting blade server operation, but multiple power module failures can cause the chassis to power off.
This policy allows you to draw more total power from the chassis. However, in case of a power module failure, the advanced management module might have to throttle down some blade servers to keep the chassis operational. Blade servers will be allowed to power on as long as the power consumed is less than or equal to the total power under this policy. If a single power module fails, processors on blade servers that are capable of throttling, will throttle in order to reduce the power consumed to less than or equal to the rated capacity of the power module. Blade servers will power up in a throttled state in some configurations. Upon restoration of power redundancy, the blade processors will return to their normal performance levels.
This policy is intended when you have two to four power modules installed and a single 110-volt or 220-volt AC power source. Each power module is on its own dedicated circuit.
- Non-redundantBlade servers will be allowed to power on as long as the power consumed is less than or equal to the total power of all installed power modules. Processors return to their normal power states when power redundancy is restored.NoteThere may be certain configurations that might result in loss of power in the domain.
See Power allocation guidelines for more information.