User's Manual

Power Management 305
If a PSU fails, it results in a non-critical health state and a PSU failure event is
generated. The removal of a PSU results in a PSU removal event.
If either event results in a loss of redundancy, based on power allocations,
a loss of redundancy event is generated.
If the subsequent power capacity or the user power capacity is greater than
the server allocations, servers have degraded performance or, in a worse case,
servers may be powered down. Both conditions are in reverse-priority order,
that is, the lower priority servers are powered down first.
Table 9-3 describes the firmware response to a PSU power down or removal as
it applies to various PSU redundancy configurations.
Table 9-2. CMC Response When a Server Power-On is Attempted
Worst Case Power
is Available
CMC Response Server
Power On
Yes No power conservation is required Allowed
No Perform power conservation:
•Power required for new server is available
• Power required for new server is not available
Allowed
Disallowed
Table 9-3. Chassis Impact from PSU Failure or Removal
PSU
Configuration
Dynamic PSU
Engagement
Firmware Response
AC Redundancy Disabled CMC alerts you of loss of AC Redundancy.
Power Supply
Redundancy
Disabled CMC alerts you of loss of Power Supply
Redundancy.
No Redundancy Disabled Decrease power to low priority servers, if needed.
AC Redundancy Enabled CMC alerts you of loss of AC Redundancy. PSUs
in standby mode (if any) are turned on to
compensate for power budget lost from the PSU
failure or removal.