C7000 power questions

[chuckk281]

Powering c7000 chassis and taking all things into consideration. Robert had some questions:

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Some C7000 Power questions:

1)      How does a C7000 / OA determine which “standby” power supply gets turned on in a N+N or N+1 configured enclosure?

2)      Customer is questioning the power info in Onboard Administrator (OA) and asking if the Power Supply values report consumed power or available power ?

3)      With the limitation of only 2 x L6-30  (30 Amp 220) circuits per rack, what is HP’s recommendation to maximize the rack with blades  (And BTW they’re looking at Integrity blades) ?

I assume this will depend on the blade configuration within each enclosure, but assume they’re limited to 2 power sticks with C19’s.

It would appear that they would be limited to a single enclosure anyway.

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Cullen shed some light on the subject:

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For question #2: It depends on which power number you’re looking at.  If it says “allocated”, then that’s the maximum power allocated to the device, not current power.  Most others are current power, unless they say something like “max input power” or “power cap” or “power available”.  You have to be careful too about what you’re reading – some things are DC (so what’s drawn FROM the power supply) while some things are AC (what the power supply draws).

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Monty also jumped in with his words of wisdom:

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1)      How does a C7000 / OA determine which “standby” power supply gets turned on in a N+N or N+1 configured enclosure?

If enclosure Dynamic Power Savings is enabled, the OA uses an enclosure power microprocessor to perform real-time control of power supplies based on actual power supply output load and actual power supply capacity.  The algorithm is proprietary, but basically puts pairs of power supplies in standby to increase the efficiency of the remaining power supplies.  The algorithm comprehends rapidly changing power supply loads and power supply fault conditions – and optimizes enclosure power efficiency while still providing redundant power.

2)      Customer is questioning the power info in OA and asking if the Power Supply values report consumed power or available power ?

The OA reports power supply output power in Watts DC. 

The OA reports enclosure power input as Present Power in Watts AC.  This input power is calculated based on power supply output power and the power supply efficiency curves based on load.

The OA reports Power Available as the Watts DC available for allocation to new power-on requests.

3)      With the limitation of only 2 x L6-30  (30 Amp 220) circuits per rack, what is HP’s recommendation to maximize the rack with blades  (And BTW they’re looking at Integrity blades) ?

I assume this will depend on the blade configuration within each enclosure, but assume they’re limited to 2 power sticks with C19’s. It would appear that they would be limited to a single enclosure anyway.

They must use the power calculator with the specific blade configuration to answer this question.

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All great information. Do you utilize the power capping and redundancy features of BladeSystem to their fullest? Let us know how you use them to save money for your company.