Setting the Inline Power Priority for a PoE Port

In a configuration where PoE power-consuming devices collectively have a greater demand for power than the PoE power supply or supplies can provide, the RUCKUS PoE device must place the PoE ports that it cannot power in standby or denied mode (waiting for power) until the available power increases. The available power increases when one or more PoE ports are powered down, or, if applicable, when an additional PoE power supply is installed in the RUCKUS PoE device.

When PoE ports are in standby or denied mode (waiting for power) and the RUCKUS PoE device receives additional power resources, by default, the device allocates newly available power to the standby ports in priority order, with the highest priority ports first, followed by the next highest priority ports, and so on. Within a given priority, standby ports are considered in ascending order, by slot number and then by port number, provided enough power is available for the ports. For example, PoE port 1/1/11 receives power before PoE port 1/2/1. However, if PoE port 1/1/11 needs 12 watts of power and PoE port 1/2/1 needs 10 watts of power, but only 11 watts of power become available on the device, the RUCKUS PoE device allocates the power to port 1/2/1 because it does not have sufficient power for port 1/1/11.

You can configure an inline power priority on PoE ports, so that ports with a higher inline power priority take precedence over ports with a low inline power priority. For example, if a new PoE port comes online and the port is configured with a high priority, if necessary (if power is already fully allocated to power-consuming devices), the RUCKUS PoE device removes power from a PoE port or ports that have a lower priority and allocates the power to the PoE port that has the higher value.

Ports that are configured with the same inline power priority are given precedence based on the slot number and port number in ascending order, provided enough power is available for the port. For example, if both PoE port 1/1/2 and PoE port 1/2/1 have a high inline power priority value, PoE port 1/1/2 receives power before PoE port 1/2/1. However, if PoE port 1/1/2 needs 12 watts of power and PoE port 1/2/1 needs 10 watts of power, but only 11 watts of power become available on the device, the RUCKUS PoE device allocates the power to PoE port 1/2/1 because it does not have sufficient power for port 1/1/2. By default, all ports are configured with a low inline power priority.

Power is removed from the ports according to the port power-down priority order. Power is removed from the port in the following scenarios:

• During power budget recovery when a PSU is removed.
• When a high priority port is powered causing a low priority port to lose power.
• When fanless mode is enabled causing a power budget reduction and consequently a budget recovery.

When power is removed, higher-numbered non-powered ports are considered first for shutdown followed by higher-numbered powered ports of the same user priority. This mechanism helps to keep the already powered ports alive as much as possible.