You can monitor a PoE switch's power supply status using CLI commands, management interfaces, or LED indicators to view power allocation, consumption, and availability.

Using Command-Line Interface (CLI)

For Cisco switches:

• show power inline: Displays the PoE status for each interface, including power allocated, power consumed, and available power for new devices .
• show power inline module <module-number>: Checks the PoE status of a specific module on modular switches .
• show switch interface inline-status: Provides detailed inline power information for all or specific interfaces .
• show power inline faulty: Lists any faulty PoE ports or devices .
• show power inline police: Displays power policing settings that may affect PoE . For Huawei switches:
• display poe information: Shows current power consumption, available power, and the maximum PoE power the switch can provide .
• display poe power-state [slot slot-id | interface interface-type interface-number]: Displays the PoE power supply status for a specific slot or interface .

Using Management Interfaces

• Web Interface or Network Management System (NMS): Most managed PoE switches provide a GUI where you can navigate to the PoE or Power Management section. This interface typically shows:
  • Power allocation per port
  • Status of connected devices (drawing power or not)
  • Real-time power consumption and available power

Using LED Indicators

• Many PoE switches have port-level LEDs that indicate PoE status:
  • Lit LED: Device is receiving power
  • Blinking LED: Device is drawing power or there is a warning
  • Off LED: No power is being supplied

Using PoE Testers

• A PoE tester can be connected between the switch and the powered device to measure real-time voltage and current, ensuring the device receives the correct power .

Key Considerations

• The total PoE power of a switch determines how many devices it can support. Each port has a maximum power limit depending on the standard (15 W for 802.3af, 30 W for 802.3at, 60–90 W for 802.3bt), .
• Power consumption of devices can vary (e.g., access points or IP phones may draw different power depending on usage), so monitoring real-time consumption is important .
• If the available PoE power is insufficient for a device's class, the switch may not supply power even if the device requires less than the class maximum . By combining CLI commands, management interfaces, LED indicators, and PoE testers, you can effectively monitor and manage the power supply status of your PoE switch, ensuring all connected devices receive adequate power.