3Com 3C16701A Switch User Manual


 
15
P
ROBLEM
S
OLVING
FOR
THE
H
UB
4
AND
4C
The OfficeConnect hub has been designed to aid you when
detecting and solving possible problems with your network.
These problems are rarely serious, the cause is usually a
disconnected or damaged cable, or incorrect configuration.
If this section does not solve your problem, contact your
supplier for information on what to do next.
Perform these actions first:
Ensure all equipment is powered on.
Power off the hubs, wait about 5 seconds and then
power on the hubs.
Check the following symptoms and solutions:
Power LED not lit.
Check your power adapter connection.
If there is still no power, you may have a faulty power
adapter which needs replacing with another OfficeConnect
power adapter.
Do not use any other power adapter
with the hub.
Alert LED continuously lit.
There is either continual
excessive use of your network (over 80%) or, more likely, a
10BASE-T port has partitioned due to a loop in your
network (in which case the corresponding Port Status LED
will be yellow). Examine your connections and remove the
loop. Each piece of equipment needs only one connection
to your OfficeConnect hub.
Port Status LED yellow for a 10BASE-T port.
It is likely
that there is a loop in your network which has caused this
port to partition. Examine your connections and remove the
loop. Each piece of equipment needs only one connection
to your OfficeConnect hub. The LED will change from
yellow to green, on receiving a valid packet on the port.
Link between two OfficeConnect hubs not working.
Check your hub connections; follow the information given
for your hub. With 10BASE-T it is likely an Uplink/Normal
switch is incorrectly set. With 10BASE-2 it is likely a
terminator (end piece) is not properly fitted; this would
cause the Coax Port Status LED to light yellow (partition).
AUI/COAX Port Status LED not lit when external
transceiver in use.
Check the AUI cable is correctly
connected to the hub and to the external transceiver. Ensure
both slide locks are engaged.
AUI/COAX Port Status LED yellow when the 10BASE-2
port is not being used.
The port has partitioned. This is
correct operation.
3C16700.book Page 15 Wednesday, July 7, 1999 5:46 PM