H3C Technologies H3C MSR 50 - Manual (Page 176)

If PoE supplies power to PSEs, the following actions occur:
• If the PoE power is overloaded and PSE power management is not enabled, no power is supplied
to a new PSE.
• If the PoE power is overloaded and a PSE power-management-priority policy is enabled, the PSE
that has a lower priority is first disconnected to guarantee the power supply to a new PSE that has
a higher priority.
In descending order, the power-supply priority levels of a PSE are critical, high, and low.
The guaranteed remaining PoE power is the maximum PoE power minus the power allocated to the
critical PSE, regardless of whether PoE is enabled for the PSE. If this is lower than the maximum power of
the PSE, you cannot set the power priority of the PSE to critical. Otherwise, you can set the power priority
to critical, and this PSE preempts the power of the PSE that has a lower priority level. In this case, the PSE
whose power is preempted is disconnected, but its configuration remains unchanged. If you change the
priority of the PSE from critical to a lower level, other PSEs have an opportunity to be powered.
To configure PSE power management:
Step Command Remarks
421. Enter system view. system-view N/A
422. Configure a PSE power
management priority policy. By default, this policy is not
configured.
poe pse-policy priority
Optional.
423. Configure the power supply
priority for the PSE. poe priority { critical | high | low }
pse pse-id
By default, the power supply
priority for the PSE is low.
NOTE:
•
The guaranteed PoE power is used to guarantee that the key PSEs in the device can be supplied with
power all the time, without being influenced by a change of PSEs.
• The guaranteed maximum PoE power is equal to the maximum PoE power.
Configuring PoE interface power management
The power supply priority of a PD depends on the priority of the PoE interface. In descending order, the
power-supply priority levels of a PoE interface are critical, high, and low. Power supply to a PD is subject
to PoE interface power management policies.
All PSEs implement the same PoE interface power management policies. If PoE supplies power to a PD,
the following actions occur:
• If the PoE power is overloaded and PSE power management is not enabled, no power is supplied
to a new PD.
• If the PoE power is overloaded and a PSE power-management-priority policy is enabled, the PD that
has a lower priority is first disconnected to guarantee the power supply to a new PD that has a
higher priority.
The guaranteed remaining PoE power is the maximum PoE power minus the power allocated to the
critical PoE interface, regardless of whether PoE is enabled for the PoE interface. If this is lower than the
maximum power of the PoE interface, you cannot set the power priority of the PoE interface to critical.
Otherwise, you can set the power priority to critical, and this PoE interface preempts the power of the PoE
interface that has a lower priority level. In this case, the PoE interface whose power is preempted is
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