3Com 3CR17450-91, Getting Started Manual

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50 C
HAPTER
4: P
ROBLEM
S
OLVING
Solving Problems
Indicated by LEDs
If the LEDs on the Switch indicate a problem, refer to the list of suggested
solutions below.
The Unit LED does not light
Check that the power cable is firmly connected to the Switch and to the
supply outlet. If the connection is secure and there is still no power, you
may have a faulty power cord or an internal fault. Firstly, check the power
cord by:
■
Testing it in another device
■
Connecting a working power cord to the ‘problem’ device
If this does not solve the problem, contact your 3Com network supplier
for assistance.
The Unit LED will not light if the Switch 3870 is a standalone unit. If the
Switch 3870 is part of a stack, the Unit ID will be shown.
The Power/Self Test LED does not light
Check that the power cable is firmly connected to the Switch and to the
supply outlet. If the connection is secure and there is still no power, you
may have a faulty power cord or an internal fault. Check the power cord
by:
■
Testing it in another device
■
Connecting a working power cord to the ‘problem’ device
If this does not solve the problem, contact your 3Com network supplier
for assistance.
When you power on the Switch, the Power/Self Test LED lights yellow for
about ten seconds, after which it starts flashing green.
On powering on, the Power/Self Test LED remains yellow
This indicates one of the following:
■
A port has failed and has been automatically disabled. You can verify
this by checking that the Port Status LED is flashing Green/Yellow
(fast). This could be due to a loop back failure. If a port fails, the
Switch passes its Power On Self Test and continues to operate
normally.