3com 4500G Quick Setup Guide

Auto-negotiation problems will occur with 10BASE-T or 100BASE-T 
where auto-negotiation is disabled and incorrect cables are being used 
(cross-over or straight).

Auto-negotiation problems will occur with fiber if:

■

The Receiver (RX) and Transceiver (TX) cable connectors are swapped

■

Fibers are broken

■

Auto-negotiation differs at either end (a link appears at the ‘fixed’ 
end and not at the auto-negotiation end)

In the rare event of your switch unit experiencing a hardware failure, refer 
to the list of suggested solutions below.

Your switch has a fan monitoring system that will generate fan failure 
warning messages. Fan failure could potentially reduce the lifetime of the 
switch. The monitoring system polls the fan status at periodic intervals 
while the unit is powered up.

If one fan has failed in the switch, a warning message will be generated in 
the following ways:

■

The seven segment display will show a green flashing ‘f’.

■

RMON Trap 

If configured, an RMON trap is generated and sent to the management 
workstation.

■

An indication of a general hardware failure is provided through the Top 
level menu displayed when logging on to the CLI. For more detailed 
information about the failure select the display logbuffer 
command.

■

An indication of fan failure is provided through the Device Summary 
table for the specific unit. In addition all Summary tables turn red to 
indicate the fan failure.