HP J3128A AdvanceStack 10Base-T Hub-8E Installation And Reference Manual page 7

3. Check the LEDs on the hub's front panel.
When the hub is powered on, it performs a 10 second self-
diagnostic test. During the test, each LED is lit momentarily.
When the self-test completes successfully, the following
events occur:
Power LED stays on
Before self-test completes, all of the LEDs light momentarily.
The following table describes the meaning of the LEDs:
LED
Activity%
Collision%
Partition
Link/Activity
Note that the bottom of the hub also provides information
about the meaning of the LEDs for this hub.
4. Before mounting the hub, unplug it. After the hub has passed
its self-test, you are ready to mount the hub.
The BNC Partition LED will remain lit unless a
properly terminated thin coax segment is
attached. This LED does not affect the operation
of the other ports.
A Link/Activity LED stays on if a signal has been detected
through a cable connected to the corresponding port. A
Link/Activity LED turns off a signal is not detected.
Reflects the amount of traffic on the
network as a percentage.
Identifies the percentage of collisions
which shows network saturation.
Displays whether a port experienced
excessive collisions or the BNC port is not
properly terminated.
Displays the amount of network traffic for
this port.
Meaning
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