3Com PS Hub 40 Switch User Manual


 
DUA1640-5AAA02
8-2
C
HAPTER
8: P
ROBLEM
S
OLVING
Solving Problems
With the Hub
Power LED not lit.
Check your power cord connection. If the
connection is secure and there is still no power, you may have a faulty
power cord which needs replacing with another PS Hub power cord.
If you have another PS Hub, try that hub’s power cord with this hub to
isolate whether the fault is with the power cord or the hub.
Power LED yellow.
The hub has failed its self-test due to an internal
problem, you need to contact your supplier.
Port Status LED yellow (PS Hub 40) or flashing green (PS Hub 50)
for a 10Mbps transceiver module 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 stack.
Port Status LED flashing green 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 stack.
Port Status LED not lit for a port that has a connection.
There is a
problem with this connection. Check you are using a
‘Straight-through’ 10BASE-T cable which is properly connected at both
ends, is not damaged, and that the equipment it is connected to is
powered on and operating correctly.
Link between two PS Hubs not working.
Check your stack
connections; follow the information given in “Connecting PS Hubs
Together (Stacking)” on page 3-12
.
Link between two stacks not working.
Check your hub
connections; follow the information given in “Connecting Different
Hubs and Stacks to Your Hub” on page 3-16
. It is likely an MDI/MDIX
switch is incorrectly set.
Segment LEDs constantly lit.
There may be a network loop caused
by connecting the segments with:
An external switch in addition to the segment switch in a
PS Hub 50.
Multiple external switches.