3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring PoE Power Management 1015
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CAUTION:
■ Before you can configure another PoE configuration file on a POE interface,
you should first remove the original PoE configuration file applied to the PoE
interface; otherwise, your configuration will fail.
■ If a PoE configuration file is already applied to a PoE interface, you must
execute the undo apply poe-profile command to remove the application to
the interface before deleting or modifying the PoE configuration file.
■ You must use the same mode (command line or PoE configuration file) to
configure the poe max-power and poe priority commands.
Configuring PoE
Power Management
PoE power management involves PSE power management and PD power
management.
Configuring PSE Power
Management
Where the maximum PoE power may be lower than the sum of the maximum
power required by all PSEs, PSE power management is applied to guarantee power
supply to important PSE. Where the maximum PoE power of the device is higher
than the sum of the maximum power required by all PSEs, it is unnecessary to
enable PSE power management.
Power supply to the PSE is subject to PSE power management policies.
When the PoE power supplies power to the PSE,
■ By default, no power will be supplied to new PSE when the PoE power is
overloaded.
■ Under the control of a priority policy, the PSE with a lower priority is first
disconnected to guarantee the power supply to the new PSE with a higher
priority when the PoE power is overloaded.
The power priority levels of PSE include critical, high and low in descending order.
If the guaranteed remaining PoE power (guaranteed maximum PoE power - power
allocated to the critical PSE, regardless of whether PoE is enabled for the PSE) is
lower than the maximum power of the PSE, you will fail to set the power priority
of the PSE to critical. Otherwise, you can succeed in setting the power priority to
critical, and this PSE will preempt the power of the PSE with a lower priority level.
In the latter case, the PSE whose power is preempted will be disconnected, but its
configuration will remain unchanged. After you change the priority of the PSE
from critical to a lower level, other PSEs will have an opportunity of seizing power.
Configuration prerequisites
Enable PoE for the PSE.
Configuration procedure
Follow these steps to configure PSE power management:
To do... Use the command... Remarks
Enter system view system-view -