3Com 3CR17251-91 - Switch 5500G-EI Stackable Gigabit Ethernet Getting Started Manual - page 20
20
C
HAPTER
1: I
NTRODUCING
THE
S
UPER
S
TACK
4 S
WITCH
5500 F
AMILY
Unit LED
The Unit LED is a seven segment display visible on the front of the Switch.
The Unit LED can be used to diagnose hardware faults, display POST test
ID, display Stack ID, display PoE utilization and software upgrade
information. For information on using the Unit LED for problem solving,
see
“Solving Problems Indicated by LEDs”
on
page 78
.
LEDs
Table 5
lists LEDs visible on the front of the Switch, and how to read their
status according to color. For information on using the LEDs for problem
solving, see
“Checking for Correct Operation of LEDs”
on
page 40
.
Table 5 LED behavior
LED
Color
Indicates
10/100/1000BASE-TX Port LEDs
Speed
Green
A high speed (1000 Mbps) link is present, blinking off
for every packet received or transmitted.
Yellow
A low speed (10/100 Mbps) link is present, blinking
off for every packet received or transmitted.
Yellow flashing
The port has failed POST.
Off
No link is present.
Duplex
Green
Full duplex, blinking off for every packet received or
transmitted.
Yellow
Half duplex, blinking off for every packet received or
transmitted.
Yellow flashing
The port has failed POST.
Off
No link is present.
PoE
Green
Power is being delivered to the port.
Green flashing
Port power has exceeded limit or is unable to supply
power due to unit being over budget.
Yellow
PoE error, no power supplied on port.
Yellow flashing
The port has failed post.
Off
No power is being delivered.
10/100BASE-T/TX Ports LEDS
Speed
Green
A high speed (100 Mbps) link is present, blinking off
for every packet received or transmitted.
Yellow
A low speed (10 Mbps) link is present, blinking off for
every packet received or transmitted.
Yellow flashing
The port has failed POST.
Off
No link is present.