3Com 3C16951 - Manual (Page 31)

Solving Problems Indicated by LEDs 31
Solving Problems
Indicated by LEDs If the LEDs on the Switch indicate a problem, refer to Table 5 which
contains a list of possible problems and suggested solutions.
Table 5 Problems indicated by LEDs
Problem Suggested Solution
A Power LED does not
light Check that the power cable is firmly connected to the
relevant Switch unit and to the supply outlet. If the
connection is secure and there is still no power, you may
have a faulty power cord.
On powering-up, the
Power/Self Test LED
lights yellow and a
Unit LED lights green The relevant Switch unit has failed its Power On Self Test
(POST) because of an internal problem. Contact your
supplier for advice.
An Expansion Module
Status LED flashes
yellow An unrecognized Expansion Module is installed into the
relevant Switch unit. You may need to remove the
Module, or upgrade the management software used by
the Switch to a version that recognizes the Module.
Contact your supplier for further advice.
A link is connected and
yet the Status LED for
the port does not light Check that:
■
All connections are secure.
■
The devices at both ends of the link are powered-up.
■
The connection uses cross-over cable if you are
linking a 10BASE-T or 100BASE-TX port with a device
that is MDIX-only.
The Packet LED for a
10BASE-T port is lit,
but the Status LED for
that port does not
light The 10BASE-T port is connected to a
10BASE-T/100BASE-TX port or a 100BASE-TX port. Do
one of the following:
■
If the 10BASE-T port is connected to a
10BASE-T/100BASE-TX port, enable auto-negotiation
on the 10BASE-T/100BASE-TX port, or set the
10BASE-T/100BASE-TX port to 10Mbps.
■
If the 10BASE-T port is connected to a 100BASE-TX
port, move the 10BASE-T connection to a
100BASE-TX connection.
The Packet LED for an
Expansion Module is
flashing even though
there is no external
traffic on this link If you have a Matrix Module installed into your Switch,
this is normal operation. Management software in the
stack passes packets between units even if there is no
other traffic activity.
16950ua.bk Page 31 Thursday, April 29, 1999 1:28 PM