HP ProCurve 6600 Power Priority Operation, How Is Power Allocation Prioritized, When Is Power Allocation Prioritized

Power Over Ethernet (PoE/PoE+) Operation

PoE Operation

For PoE+, there must be 33 watts available for the module to begin supplying power to a port with a PD connected. A slot in a zl chassis can provide a maximum of 370 watts of PoE/PoE+ power to a module.

Disconnecting a PD from a PoE port causes the module to stop providing PoE power to that port and makes the power available to any other PoE ports that have PDs connected and waiting for power. If the PD demand for power becomes greater than the PoE power available, then power is transferred from the lower-priority ports to the higher-priority ports. (Ports not currently providing power to PDs are not affected.)

Power Priority OperationWhen Is Power Allocation Prioritized?

If a PSE can provide power for all connected PD demand, it does not use its power priority settings to allocate power. However, if the PD power demand oversubscribes the available power, then the power allocation is prioritized to the ports that present a PD power demand. This causes the loss of power from one or more lower-priority ports to meet the power demand on other, higher-priority ports. This operation occurs regardless of the order in which PDs connect to the module’s PoE-enabled ports.

How Is Power Allocation Prioritized?

There are two ways that PoE power is prioritized:

■Using a priority class method, a power priority of Low (the default), High, or Critical is assigned to each enabled PoE port.

■Using a port-number priority method, a lower-numbered port has priority over a higher-numbered port within the same configured priority class, for example, port A1 has priority over port A5 if both are configured with High priority.

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