1-11
Cisco CGS 2520 Hardware Installation Guide
OL-31444-01
Chapter 1 Product Overview
LEDs
Port LEDs
RJ-45 ports and SFP module slots have port LEDs. Port LEDs, as a group or individually, provide
information about the switch and about the individual ports.
PoE LED
Table 1-7
RJ-45 and USB Console Port LEDs
LED
Color
Description
RJ-45 console port
Green
RJ-45
console port is active.
; USB console port LED is off
Off
Port is not active; USB console port is active
USB console port
Green
USB console port is active; RJ-45 console port LED is off
Off
Port is not active; RJ-45 console port is active
Table 1-8
Meaning of Port LED Colors
LED Color
Meaning
Off
No link or port was administratively shut down
Green
Link present but not sending or receiving data
Blinking green
Activity. Port is sending or receiving data
Alternating
green-amber
Link fault. Error frames can affect connectivity, and errors such as excessive
collisions, CRC errors, and alignment and jabber errors are monitored for link
faults
Amber
Port is blocked by Spanning Tree Protocol (STP) and is not forwarding data.
After a port is reconfigured, the port LED is amber for up to 30 seconds as
STP searches for loops.
Table 1-9
PoE LED
Color
Meaning
Off
PoE/PoE+ not enabled
Green
PoE/PoE+ enabled and ports are functioning correctly
Alternating green and amber
PoE/PoE+ enabled but power is disconnected or has failed on a
low-priority port
Blinking amber
PoE/PoE+ enabled but power is disconnected or has failed on a
high-priority port
Amber
PoE/PoE+ enabled and a PoE/PoE+ circuit failure is detected
