Cisco Catalyst 3650 Series, Command Reference Manual

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2 The device automatically sets the power usage of the device by using CDP power negotiation or by the
IEEE classification and LLPD power negotiation.
If you do not manually configure the cutoff-power value, the device automatically determines it by using CDP
power negotiation or the device IEEE classification and LLDP power negotiation. If CDP or LLDP are not
enabled, the default value of 30 W is applied. However without CDP or LLDP, the device does not allow
devices to consume more than 15.4 W of power because values from 15400 to 30000 mW are only allocated
based on CDP or LLDP requests. If a powered device consumes more than 15.4 W without CDP or LLDP
negotiation, the device might be in violation of the maximum current
Imax limitation and might experience
an Icut fault for drawing more current than the maximum. The port remains in the fault state for a time before
attempting to power on again. If the port continuously draws more than 15.4 W, the cycle repeats.
When a powered device connected to a PoE+ port restarts and sends a CDP or LLDP packet with a power
TLV, the device locks to the power-negotiation protocol of that first packet and does not respond to power
requests from the other protocol. For example, if the device is locked to CDP, it does not provide power to
devices that send LLDP requests. If CDP is disabled after the device has locked on it, the device does not
respond to LLDP power requests and can no longer power on any accessories. In this case, you should restart
the powered device.
If power policing is enabled, the device polices power usage by comparing the real-time power consumption
to the maximum power allocated on the PoE port. If the device uses more than the maximum power allocation
(or
cutoff power ) on the port, the device either turns power off to the port, or the device generates a syslog
message and updates the LEDs (the port LEDs are blinking amber) while still providing power to the device.
• To configure the device to turn off power to the port and put the port in the error-disabled state, use the
power inline police
interface configuration command.
• To configure the device to generate a syslog message while still providing power to the device, use the
power inline police action log command.
If you do not enter the
action log
keywords, the default action is to shut down the port, turn off power to it,
and put the port in the PoE error-disabled state. To configure the PoE port to automatically recover from the
error-disabled state, use the
errdisable detect cause inline-power
global configuration command to enable
error-disabled detection for the PoE cause and the errdisable recovery cause inline-power interval interval
global configuration command to enable the recovery timer for the PoE error-disabled cause.
If policing is disabled, no action occurs when the powered device consumes more than the maximum
power allocation on the port, which could adversely affect the device. Caution
You can verify your settings by entering the show power inline police privileged EXEC command.
Examples This example shows how to enable policing of the power consumption and configuring the device to generate
a syslog message on the PoE port on a device:
Device(config)# interface gigabitethernet1/0/2
Device(config-if)#
power inline police action log
Command Reference, Cisco IOS XE Everest 16.5.1a (Catalyst 3650 Switches)
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power inline police