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Configuring PI power management
PI power management enables the PSE to perform priority-based PI power management in PSE
power overload situations. In descending order, the power-supply priority levels of a PI are critical,
high, and low. The PD priority is determined by the priority of the PI to which the PD is connected. All
PSEs use the same PI power management mechanism.
If you do not enable PI power management, the PSE might become overloaded. PSE power
overload triggers the PoE self-protection mechanism to stop power supply to all PDs.
If you enable PI power management, the PSE stops power supply to existing PDs causing overload
or performs priority-based operations for new PDs causing overload:
Priority
PSE operations
Low The PSE does not supply power to a new PD.
High
• If low-priority PDs exist, the PSE stops power supply to the existing
low-priority PDs, and supplies power to the new PD.
• If no low-priority PDs exist, the PSE does not supply power to the new PD.
Critical
• If low-priority or high-priority PDs exist, the PSE stops power supply to the
existing low-priority or high-priority PDs, and supplies power to the new PD.
• If no low-priority or high-priority PDs exist, the PSE does not supply power
to the new PD.
Configuration for PIs whose power is preempted remains unchanged.
If multiple new PDs require power supply, the PSE supplies power to PDs in priority descending
order. For PDs with the same priority, the one with the smallest PD ID takes precedence.
If multiple existing PDs need to be stopped with power supply, the PSE stops power supply to PDs in
priority ascending order. For PDs with the same priority, the one with the greatest ID takes
precedence.
The PSE guarantees its critical PIs uninterruptable power by reserving guaranteed PSE power. If
you want a PI to be allocated with uninterruptable power, configure the PI with critical priority.
Otherwise, configure the PI with high or low priority to ensure that other PIs can be supplied with
power.
Before you configure a PI with critical priority, make sure the remaining guaranteed power is greater
than or equal to the maximum power of the PI. The remaining guaranteed PSE power is the
maximum PSE power minus the maximum power for PoE-enabled and PoE-disabled critical PIs.
To configure PI power management:
1. Enter system view.
system-view
N/A
2. Enable
management.
poe pd-policy priority
By default, PI power management
is disabled.
3. Enter PI view.
interface
interface-type
interface-number
N/A