User's Manual

Power Management 227
Power Conservation and Power Budget Changes
The CMC performs power conservation when the user-configured maximum
power limit is reached. When the demand for power exceeds the set power
limit, the CMC reduces power to servers assigned a lower priority in order to
free power for higher priority servers and other modules in the chassis.
If all or multiple slots in the chassis are configured with the same priority
level, the CMC decreases power to servers by increasing slot number order.
For example, if the servers in slots 1 and 2 have the same priority level, the
power for the server in slot 1 is decreased before that of the server in slot 2.
NOTE: You can assign a priority level to each of the servers in the chassis by giving
each server a number from 1 through 9. The default priority level for all servers is 1.
The lower the number, the higher the priority level. For instructions on assigning
server priority levels, see "Using RACADM" on page 249.
PSU Failure With a No Redundancy Policy
The CMC decreases power to servers when an insufficient power event
occurs, such as a PSU failure. After decreasing power on servers, the CMC re-
evaluates the power needs of the chassis. Power for higher priority servers is
restored incrementally while power needs remain within the power budget.
NOTE: To set the redundancy policy, see "Configuring Power Budget and
Redundancy" on page 245.