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 FastIron 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 FastIron PoE device.
When PoE ports are in
standby
or
denied
mode (waiting for power) and the FastIron 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 should receive 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 FastIron 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 FastIron 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
FastIron 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.
Command syntax for setting the inline power priority for a PoE port
To configure an inline power priority for a PoE port on a FastIron PoE device, use the
inline power
priority
command as shown in the following example.
ICX7250-48P Switch# configure terminal
ICX7250-48P Switch(config)# interface ethernet 1/1/1
ICX7250-48P Switch(config-if-e1000-1/1/1)# inline power
decouple-datalink Decouple PoE from data link operational behavior
power-by-class Allocate power based on class of the power devices
power-limit Allocate power based on specified limit
priority Priority class for the purpose of power management
<cr>
ICX7250-48P Switch(config-if-e1000-1/1/1)# inline power priority
DECIMAL Priority value 1..3 (highest..lowest)
<cr>
ICX7250-48P Switch(config-if-e1000-1/1/1)# inline power priority 1
Warning: Inline power configuration on port 1/1/1 has been modified.
In the previous example, the command enables inline power on interface ethernet 1 in slot 1 of unit 1
and sets the inline power priority level to high.
Syntax:
[no] inline power priority
priority num
The
priority num
parameter is the inline power priority number. The default is 3 (low priority). You can
specify one of the following values:
Setting the inline power priority for a PoE port
FastIron Ethernet Switch Administration Guide
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