Cisco Catalyst 2960 Series, Руководство по настройке

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never
— The switch disables powered-device detection and never powers the PoE port even if an
unpowered device is connected. Use this mode only when you want to make sure that power is never
applied to a PoE-capable port, making the port a data-only port.
For most situations, the default configuration (auto mode) works well, providing plug-and-play operation. No
further configuration is required. However, perform this task to configure a PoE port for a higher priority, to
make it data only, or to specify a maximum wattage to disallow high-power powered devices on a port.
Power Monitoring and Power Policing
When policing of the real-time power consumption is enabled, the switch takes action when a powered device
consumes more power than the maximum amount allocated, also referred to as the
cutoff-power value .
When PoE is enabled, the switch senses the real-time power consumption of the powered device. The switch
monitors the real-time power consumption of the connected powered device; this is called
power monitoring
or power sensing . The switch also polices the power usage with the power policing feature.
Power monitoring is backward-compatible with Cisco intelligent power management and CDP-based power
consumption. It works with these features to ensure that the PoE port can supply power to the powered device.
The switch senses the real-time power consumption of the connected device as follows:
1
The switch monitors the real-time power consumption on individual ports.
2 The switch records the power consumption, including peak power usage. The switch reports the information
through the CISCO-POWER-ETHERNET-EXT-MIB.
3 If power policing is enabled, the switch polices power usage by comparing the real-time power consumption
to the maximum power allocated to the device. The maximum power consumption is also referred to as
the
cutoff power on a PoE port.
If the device uses more than the maximum power allocation on the port, the switch can either turn off
power to the port, or the switch can generate a syslog message and update the LEDs (the port LED is now
blinking amber) while still providing power to the device based on the switch configuration. By default,
power-usage policing is disabled on all PoE ports.
If error recovery from the PoE error-disabled state is enabled, the switch automatically takes the PoE port
out of the error-disabled state after the specified amount of time.
If error recovery is disabled, you can manually re-enable the PoE port by using the
shutdown
and
no
shutdown interface configuration commands.
4
If policing is disabled, no action occurs when the powered device consumes more than the maximum
power allocation on the PoE port, which could adversely affect the switch.
Maximum Power Allocation (Cutoff Power) on a PoE Port
When power policing is enabled, the switch determines one of the these values as the cutoff power on the
PoE port in this order:
1
Manually when you set the user-defined power level that the switch budgets for the port by using the
power inline consumption default wattage
global or interface configuration command
2 Manually when you set the user-defined power level that limits the power allowed on the port by using
the
power inline auto max max-wattage
or the
power inline static max max-wattage
interface
configuration command
3 Automatically when the switch sets the power usage of the device by using CDP power negotiation or by
the IEEE classification and LLDP power negotiation.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
89
Information about PoE