To display information about the inline power for all interfaces or for a specific interface, use the show power inline Privileged EXEC mode command. interface-id—Specifies an interface ID. Show information for all ports. auto—Turns on the device discovery protocol and applies power to the device. Shows Yes for ports enabled to support PoE (the default) and No for ports on which PoE is disabled. Toggle the hierarchy tree under Learn About Power over Ethernet (PoE). PSE Power Management: means the power supply management mode (automatic, preempt, non-preempt).
[pdf] If your Cisco switch PoE is not working, the most common causes are an exhausted PoE power budget, a disabled inline power configuration, physical cable faults, incompatible powered devices (PD), or a crashed PoE controller. When a problem occurs with PoE, in most cases, the error symptom can be simply shown as the PoE switch not providing power, and the powered devices will stop. This guide is for troubleshooting Power over Ethernet (PoE) in the Catalyst 3750-E, 3750, 3560-E, and 3560 switch product families. Topics related to earlier PoE switches are also included. However, when PoE fails, it can disable critical infrastructure like IP phones, wireless access points, and security cameras. PoE is a networking feature defined by the IEEE 802.
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