Troubleshooting Ring Problems; Problems Adding A New Station To An Operating Ring - 3Com CoreBuilder 5000 User Manual

Troubleshooting
Ring Problems
Problems Adding a
New Station to an
Operating Ring
This section provides remedies for problems you could encounter when
working with Token Ring Networks.
Problems may arise when using the lobe ports to add a new station to
an operating ring. The station does not initialize properly on the ring,
and reports that it has failed diagnostic testing. Problems of this type
are generally traced to horizontal cabling that attaches the station to
the hub.
To resolve a 'failed diagnostic' ring problem:
1 Verify that the port is enabled on the module that the failing station is
attached to. If the front panel LED corresponding to this port is:
On or blinking, go to step 2.
Off, the port is disabled. Enable the port to allow the station to
attach to the ring.
2 Verify that the station adapter card is set to the same ring speed as the
hub port.
3 Verify the presence of the DC phantom current generated by the
station when requesting attachment to the ring.
Observe the front panel LED of the port connected to the failing
station. The LED should be blinking when no cable is attached,
or when the station has not yet requested attachment to the
ring.
Once the station attaches to the ring, the LED should be on
continuously. If the LED does not stay on continuously, the
station is not requesting attachment or is unable to attach to the
ring.
Check the cabling and confirm that the station is operating
properly.
4 Verify that the cables being used to connect the station to the hub are
secure. Be sure not to exceed the maximum lobe cable distances
recommended in Chapter
attaching cables meets the requirements described in
If the adapter is set for the incorrect speed, the station may report that
it has inserted itself on the ring, even though the module has
prevented the station from inserting.

Troubleshooting Ring Problems

2. Also, verify that the pinout of the
5-5
Appendix A.