Configuring the PoE port priority

Syntax:


interface <port-list> power-over-ethernet [critical | high | low]

Reconfigures the PoE priority level on <port-list>. For a given level, ports are prioritized by port number in ascending order. For example, if ports 1-24 have a priority level of critical, port 1 has priority over ports 2-24.

If there is not enough power available to provision all active PoE ports at a given priority level, the lowest-numbered port at that level is provisioned first. For chassis switches, the lowest-numbered port at that level starting with module A, then B, C, and so on is provisioned. PoE priorities are invoked only when all active PoE ports cannot be provisioned (supplied with PoE power)

`Critical`	Specifies the highest-priority PoE support for `<port-list>`. The active PoE ports at this level are provisioned before the PoE ports at any other level are provisioned.
`High`	Specifies the second priority PoE support for `<port-list`>. The active PoE ports at this level are provisioned before the `Low` priority PoE ports are provisioned.
`Low`	(Default) Specifies the third priority PoE support for `<port-list>`. The active PoE ports at this level are provisioned only if there is power available after provisioning any active PoE ports at the higher priority levels.

The following table shows some examples of PoE priority configuration.

Table 6: PoE priority operation on a PoE module
Port	Priority setting	Configuration command¹ and resulting operation with PDs connected to ports C3 through C24
C3 - C17	Critical	In this Example:, the following CLI command sets ports C3 to C17 to Critical: switch(config)# interface c3-c17 power-over-ethernet critical The critical priority class always receives power. If there is not enough power to provision PDs on all ports configured for this class, no power goes to ports configured for high and low priority. If there is enough power to provision PDs on only some of the critical-priority ports, power is allocated to these ports in ascending order, beginning with the lowest-numbered port in the class, which, in this case, is port 3.
C18 - C21	high	In this Example:, the following CLI command sets ports C19 to C22 to high: switch(config)# interface c19-c22 power-over-ethernet high The high priority class receives power only if all PDs on ports with a critical priority setting are receiving power. If there is not enough power to provision PDs on all ports with a high priority, no power goes to ports with a low priority. If there is enough power to provision PDs on only some of the high-priority ports, power is allocated to these ports in ascending order, beginning, in this Example:, with port 18, until all available power is in use.
C22 - C24	low	In this Example:, the CLI command sets ports C23 to C24 to low²: switch(config)# interface c23-c24 power-over-ethernet low This priority class receives power only if all PDs on ports with high and critical priority settings are receiving power. If there is enough power to provision PDs on only some low- priority ports, power is allocated to the ports in ascending order, beginning with the lowest-numbered port in the class (port 22, in this case), until all available power is in use.
C1 - C2	N/A	In this Example:, the CLI command disables PoE power on ports C1 to C2: switch(config)# no interface c1-c2 power-over-ethernet There is no priority setting for the ports in this Example:.

For a listing of PoE configuration commands with descriptions, see Configuring PoE operation.

In the default PoE configuration, the ports are already set to low priority. In this case, the command is not necessary.