Thesystem reserves enough power to boot a server in each slot, even if that slot is empty. This reserved
powercannot be leveragedby servers requiring more power. Blades that fail to comply with the power
capare penalizedor shut down.
Note
Configuring Power Groups

Power Groups

Apower group is a set of chassis that all draw power from the same power distribution unit (PDU). In Cisco
UCSManager, you can create power groups that include one or more chassis and then set a peak power cap
inAC wattsfor that powergrouping.
Institutingpower capping at the chassis level requires the following:
• IOM, CIMC, and BIOS version 1.4 or higher
• 2 PSUs
Thepeak power cap is a static value that represents the maximum power available to all blade servers within
agiven power group. If you add or remove a blade from a power group, but do not manually modify the peak
powervalue, the power group adjuststhe peak power cap to accommodate the basic power-on requirements
ofall blades within that power group.
Aminimum of 3788 AC watts should be set for each chassis. This converts to 3400 watts of DC power, which
isthe minimum amount of power required to power a fully-populated chassis.
Ifinsufficient power is available, Cisco UCS Managerraises an alert.
Oncea chassis is added to a power group, every service profile associated with that chassis also becomes part
ofthat power group. Similarly, if you add a new blade to a chassis, that blade inherently becomes part of the
chassis'power group.
Creatinga power group is not the same as creating a server pool. However, you can populate a server pool
withmembers of the same power group by creating a power qualifier and adding it to server pool policy.
Note

Creating a Power Group

Before You Begin
Makesure the globalpower allocation policy is set to Policy Driven Chassis GroupCap on the Global
Policiestab.
Cisco UCS Manager GUI Configuration Guide, Release 2.0
566 OL-25712-04
Configuring Policy-Driven Chassis Group Power Capping