Users Guide

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.
The following table provides the firmware response to a PSU power down or removal as it applies to
various PSU redundancy configurations.
Table 39. Chassis Impact from PSU Failure or Removal
PSU Configuration Dynamic PSU
Engagement
Firmware Response
Grid Redundancy Disabled CMC alerts you of loss of Grid 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.
Grid Redundancy Enabled CMC alerts you of loss of Grid Redundancy. PSUs in
standby mode (if any) are turned on to compensate for
power budget lost from the PSU failure or removal.
Power Supply
Redundancy
Enabled CMC alerts you of loss of Power Supply Redundancy.
PSUs in standby mode (if any) are turned on to
compensate for power budget lost from PSU failure or
removal.
No Redundancy Enabled Decrease power to low priority servers, if needed.
Power Supply and Redundancy Policy Changes in System Event Log
Changes in the power supply state and power redundancy policy are recorded as events. Events related
to the power supply that record entries in the system event log (SEL) are power supply insertion and
removal, power supply input insertion and removal, and power supply output assertion and de-assertion.
The following table lists the SEL entries that are related to power supply changes:
Table 40. SEL Events for Power Supply Changes
Power Supply Event System Event Log (SEL) Entry
Insertion Power supply <number> is present.
Removal Power supply <number> is absent.
Grid or Power Supply Redundancy lost Power supply redundancy is lost.
Grid or Power Supply Redundancy
regained
The power supplies are redundant.
Input power received The input power for power supply <number> has been
restored.
Input power lost The input power for power supply <number> has been lost.
DC output produced Power supply <number> is operating normally.
DC output lost Power supply <number> failed.
Input over-voltage An over voltage fault detected on power supply <number>.
Input under-voltage An under voltage fault detected on power supply <number>.
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