CANOGA PERKINS 9120 Gigabit Ethernet Media Converter - Manual (Page 23)

Canoga Perkins
9120 Gigabit Ethernet Media Converter 4-1
Chapter 4
Troubleshooting
In the case of the 9120 Media Converter, a hybrid device, there are two LNK LED indicators, marked
User LNK and Extension LNK. When the 9120 Media Converter is put into service, if all cables are
correctly connected and there are User and Extension devices attached to the cable, both LNK
indicators should illuminate. If either LNK Indicator does not illuminate, check the appropriate
attached cable and remote transmitter to ensure they are connected properly.
This implies that if the LNK indicator is illuminated on the local device, the remote transmitter, the
attached cable and the local receiver are operational. Thus, if the RMTF LED indicator is
illuminated, it indicates a problem with either the local fiber transmitter, the attached cable, or the
remote fiber receiver.
The 9120 Media Converter's Link Loss Forwarding (LLF) feature will disable the Extension or User
transmitter whenever the Extension LNK LED indicator is off. This allows the fiber failure to be
sensed by a management agent at the remote User port as a User Link failure. Therefore, whenever
the User transmitter appears to be off, check the receive Extension link cable connections to the 9120
media converter and ensure the F/LNK LED indicator is illuminated.
If the Power LED indicator and both LNK indicators are illuminated, and the RMTF indicator is off,
you can assume with some assurance that the problem exists elsewhere. Data transfer through the
9120 Media Converter can only take place when both LNK indicators are illuminated and the RMTF
indicator is off. The most common cause of network problems, once physical layer problems are
resolved, is software configurations.
In addition, check that the total link loss is within the allowable fiber optic loss budget, and that the
proposed application is within normal IEEE 802.3 Propagation Delay Budget.
If this still does not solve the problem, call the Canoga Perkins Service Department at (818) 718-
6300.