Changing the threshold for generating a power notice

You can configure one of the following thresholds:

  • A global power threshold that applies to all ports on the switch. This setting acts as a trigger for sending a notice when the PoE power consumption on any PoE port installed in the switch crosses the configured global threshold level. (Crossing the threshold level in either direction—PoE power usage either increasing or decreasing— triggers the notice.) The default setting is 80%.

  • A per-slot power threshold that applies to an individual PoE module installed in the designated slot. This setting acts as a trigger for sending a notice when the module in the specified slot exceeds or goes below a specific level of PoE power consumption.


Some switches covered by this manual provide a single fixed slot.


power-over-ethernet [slot < slot-id-range >] threshold <1-99>

This command specifies the PoE usage level (as a percentage of the PoE power available on a module) at which the switch generates a power usage notice. This notice appears as an SNMP trap and a corresponding Event Log message and occurs when a PoE module's power consumption crosses the configured threshold value. That is, the switch generates a notice whenever the power consumption on a module either exceeds or drops below the specified percentage of the total PoE power available on the module.

This command configures the notification threshold for PoE power usage on either a global or per-module (slot) basis.

Without the [slot PoE <slot-id-range>] option, the switch applies one power threshold setting on all PoE modules installed in the switch.


Suppose slots A, B, and C each have a PoE module installed. In this case, executing the following command sets the global notification threshold to 70% of available PoE power:

switch(config)# power-over-ethernet threshold 70

With this setting, if module B is allocated 100 watts of PoE power and is using 68 watts, and then another PD is connected to the module in slot B that uses 8 watts, the 70% threshold of 70 watts is exceeded. The switch sends an SNMP trap and generates this Event Log message:

Slot B POE usage has exceeded threshold of 70%.

If the switch is configured for debug logging, it also sends the Event Log message to the configured debug destination(s).

On any PoE module, if an increasing PoE power load (1) exceeds the configured power threshold (which triggers the log message and SNMP trap), and then (2) later decreases and drops below the threshold again, the switch generates another SNMP trap, plus a message to the Event Log and any configured Debug destinations.

To continue the preceding Example:, if the PoE power usage on the PoE module in slot B drops below 70%, another SNMP trap is generated and you will see this message in the Event Log:

Slot B POE usage is below threshold of 70%.

For a message listing, please see the event log message reference guide for your switch. Go to; auto search the model number for your switch, for Example: “Aruba Switch 2920”, then select the device from the list and click on Product manuals. Click on the “User guide” link under Manuals.

(Default Global PoE Power Threshold: 80). By using the [slot <slot-id-range>] option, you can specify different notification thresholds for different PoE modules installed in the switch. For example, you could set the power threshold for a PoE module in slot “A” to 75% and the threshold for the module in slot “B” to 68% by executing the following two commands:

switch(config)# power-over-ethernet slot a threshold 75
switch(config)# power-over-ethernet slot b threshold 68

The last threshold command affecting a given slot supersedes the previous threshold command affecting the same slot. Thus, executing the following two commands in the order shown sets the threshold for the PoE module in slot “D” to 75%, but leaves the thresholds for any PoE modules in the other slots at 90%.

switch(config)# power-over-ethernet threshold 90
switch(config)# power-over-ethernet slot d threshold 75

If you reverse the order of the above two commands, all PoE modules in the switch will have a threshold of 90%.