3Com 3CRDSF9PWR manual LED Status, Indicators, Describes the meanings of the LEDs

18CHAPTER 1: GETTING STARTED

LED Status	The OfficeConnect Managed Fast Ethernet PoE switch provides LED
Indicators	indicators on the front panel for your convenience to monitor the switch.
	Table 2 describes the meanings of the LEDs.
	Table 2 Description on the LEDs of the OfficeConnect Managed Fast Ethernet
	PoE Switch
	LED	Label	Status	Description
	Power	Power	Green	The switch starts normally. The LED flashes when
				the system is performing power-on self test (POST)
				or firmware is being upgraded.
			Yellow	The system has failed the POST.
			OFF	The switch is powered off.
	10/100	Link/	Green	The port works at the rate of 100 Mbps; the LED
	BASE-TX	Activity		flashes quickly when the port is sending or receiving
	Ethernet port			data.
	status
			Yellow	The port works at the rate of 10 Mbps; the LED
				flashes quickly when the port is sending or receiving
				data.
			OFF	The port is not connected.
	10/100/1000	Link/	Green	The port works at the rate of 1000 Mbps; the LED
	BASE-T	Activity		flashes quickly when the port is sending or receiving
	Ethernet port			data.
	status
			Yellow	The port works at the rate of 10/100 Mbps; the LED
				flashes quickly when the port is sending or receiving
				data.
			OFF	The port is not connected.
	Duplex mode	Duplex	Yellow	The port is in full duplex mode.
			OFF	The port is not connected, or is in half duplex mode.
	100/1000	Module	Green	An SFP module is inserted.
	Base SFP port	Active
			OFF	An SFP module is not inserted or is not recognized.
	status
	PoE status	PoE	Green	Delivering power. The LED flashes if a fault occurs.
		Status
			OFF	Not delivering power.