3Com LinkBuilder MSH User Manual page 19

The LinkBuilder MSH 4 Port Ethernet Bridge Module 1-5
Below its top ejector, the bridge has a panel of LEDs that indicate
bridge activity, as shown in Figure 1-3.
Each port has a row of three LEDs; transmit (TX), receive (RX) and
enabled (EN). Ports with numbers signify the Ethernet bus in the
LinkBuilder MSH chassis to which the port is connected. The
unnumbered row is for the external port, the Transceiver Module.
Figure 1-3 The Module's LEDs
You can also use the LEDs to help with diagnosing faults on your
Using The LEDs For Fault
system, for more information refer to
Diagnosis on page 6-3.
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