Additional servers can be powered up in the modular enclosure only if sufficient power is available. The
System Input Power Cap can be increased any time up to a maximum value of 5000 Watt to allow the
power up of additional servers.
Changes in the modular enclosure that reduce the power allocation are:
• Server turned off
• I/O module turned off
• Storage adapters, PCIe cards, physical disk drive, and main board turned off
• Transition of the chassis to a turned-off state
You can reconfigure the System Input Power Cap when the chassis is either turned on or turned off.
Server Slot Power Priority Settings
CMC allows you to set a power priority for each of the four server slots in an enclosure. The priority
settings are 1 (highest) through 9 (lowest). These settings are assigned to slots in the chassis, and the
priority of the slots is inherited by any server inserted in that slot. CMC uses slot priority to preferentially
budget power to the highest priority servers in the enclosure.
According to the default server slot priority setting, power is equally apportioned to all slots. Changing
the slot priorities allows administrators to prioritize the servers that are given preference for power
allocations. If the more critical server modules are left at their default slot priority of 1, and the less critical
server modules are changed to lower priority value of 2 or higher, the priority 1 server modules is
powered on first. These higher priority servers get their maximum power allocation, while lower priority
servers may be not be allocated enough power to run at their maximum performance or they may not
even power on at all, depending on how low the system input power cap is set and the server power
requirements.
If an administrator manually powers on the low priority server modules before the higher priority ones,
then the low priority server modules are the first modules to have their power allocation lowered down
to the minimum value, in order to accommodate the higher priority servers. Therefore, after the available
power for allocation is exhausted, CMC reclaims power from lower or equal priority servers until they are
at their minimum power level.
NOTE: I/O module, fans, and mainboard, physical disk drives, storage adapters are given the highest
priority. CMC reclaims power only from the lower-priority devices to meet the power needs of a
higher-priority device or server.
Assigning Priority Levels To Servers
When additional power is required, server priority levels determine which servers the CMC draws power
from.
NOTE: The priority you assign to a server is linked to a server's slot and not to the server itself. If you
move the server to a new slot, you must re-configure the priority for the new slot location.
NOTE: To perform power management actions, you must have the Chassis Configuration
Administrator privilege.
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