A power controller for power sourcing equipment in a distributed power network provides power down policies and priority in the event of a power supply failure. The power down priority and policy permits implementation of a rapid decrease in the power demand of the distributed power network to avoid overload of a backup power supply. The priority may be derived based on the relative position of port information in a linked list. Devices associated with a high priority can remain powered in response to a main power supply failure, while lower priority devices can be rapidly powered down to reduce the overall load demand on the backup power supply. The ability to configure ports on the basis of priority and available policies provides a flexible and simple implementation of a response in the event of a main power supply failure.