Cabletron Systems FR-3000 User Manual - page 17
The FR-3000 Fiber Optic Repeater uses Cabletron Systems’ built-in visual diagnostic and
status monitoring system LANVIEW. Using LANVIEW, a network troubleshooter can
quickly scan the LANVIEW LEDs to observe network status or to diagnose network prob-
lems and determine which node or segment is faulty.
The following discusses the function and the purpose of each LANVIEW LED on the FR-
3000. Refer to Figure 4-2.
Power (PWR) LED
When lit, this LED indicates that the FR-3000 is receiving power. If this LED is not lit, the
problem may be with the input power, or in the FR-3000.
Transceiver Power (XCVR PWR) LED
When lit, this LED indicates that the FR-3000 is providing power to the external transceiver
connected to the FR-3000. If this LED is not lit, power is not being provided to the trans-
ceiver and the problem may be in the FR-3000.
Jam (JAM) LED
This LED normally flashes on and off to indicate that the FR-3000 is propagating a colli-
sion from the segment on which the collision is occurring to the other segment connected
to the repeater. When this LED flashes, a pattern of 1,0 is sent to each segment to indicate
that a collision is occurring on one of the segments. What will be observed is that the COL-
LISION LED for one segment will flash, indicating a collision, causing the JAM LED to
flash.
Fault (FAULT) LED
When the FAULT LED is lit, this indicates that the FR-3000 electrically disconnected seg-
ment 2 from the network because 32 consecutive collisions have occurred on that segment,
or because the collision detector was on for more than 2.4 ms. The FAULT LED will go
out after one packet is transmitted onto the segment with the fault without causing a colli-
sion.
Optical Link (LINK OK) LED
When lit, this LED indicates that an optical link has been established between the two FR-
3000s connected with the fiber optic cable. The LED will remain lit as long as an optical
link is maintained between the two repeaters. To ensure that an optical link is maintained,
the transmitters in each repeater generate a 1MHz idle signal when they are not transmitting
data.
Receive (RECEIVE) LED
This LED normally flashes on and off to indicate that the FR-3000 is repeating the data
packet being received from that segment. The rate at which the LED is flashing will in-
crease as network activity increases.
Collision (COLLISION) LED
This LED normally flashes on and off to indicate that a collision is occurring on the indi-
cated segment. The rate at which the LED is flashing will increase as network activity in-
creases since more collisions are likely to occur.