48 
Status 
Description 
Port mode LED  Ethernet 
ort status LED
Flashing green (1 Hz) (PoE mode, 
supported by S5120-28C-PWR-EI 
and S5120-52C-PWR-EI only) 
Steady green  PoE power supply is normal. 
Flashing green (1 Hz) 
The device attached to the port 
requires power higher than the 
maximum or currently available PoE 
output power on the port. 
Steady yellow 
The port is experiencing a PoE 
failure.  
The devices attached to the port are 
not powered devices (PDs), so the 
port does not supply power. 
Flashing yellow (3 Hz)  POST has failed on the port. 
Off 
The port is not supplying PoE 
power. 
Steady yellow (duplex mode) 
Steady green 
The port is operating in full duplex 
mode. The port status LED fast 
flashes when the port is sending or 
receiving data. 
Steady yellow 
The port is operating in half duplex 
mode. The port status LED fast 
flashes when the port is sending or 
receiving data. 
Flashing yellow (3 Hz)  POST has failed on the port. 
Off  No link is present on the port. 
 
SFP port status LED 
Each 1000Base-X SFP port has a status LED to show port operating status and activities. The port mode 
LED shows the type of port status information that the port status LEDs are showing. 
Table 19 SFP port status LEDs description 
Status 
Description 
Port mode LED  Ethernet 
ort status LED
Steady green (rate mode) or 
flashing green (1 Hz, PoE mode) 
Steady green 
The port is operating at 1000 Mbps. 
The port status LED fast flashes when 
the port is sending or receiving data.
Flashing yellow (3 Hz)  POST has failed on the port. 
Off  No link is present on the port.