Cabletron Systems TRBMIM-T, User Manual

Page: 59 / 74

MONITORING AND TROUBLESHOOTING
5-9
• Ensure that the ERR LED, or equivalent LED, on each MIM in the
MMAC is not lit. Reset MIMs with lit ERR LEDs, which may be all
that is necessary to resolve the problem.
• Verify that the LNK LED on the TPIM installed in the Station
receptacle is green. If it is not green, ensure that the attached cable is
functional. Also, verify that the TPIM is correctly configured for
Station application. See Section 4.1.1 for information about
configuring TPIMs.
• Verify that both the Station and FNB rings are operating at the correct
speed using the 16Mb LEDs. All MIMs operating on a common FNB
ring must be running at the same speed.
• Ensure that you have correctly configured ring numbers. See the
TRBMIM/TRBMIM-T Local Management User’s Guide for
information about how to configure ring numbers for the FNB and
bridge Station ports. Follow these guidelines when assigning ring
numbers:
- If you want multiple bridges interfacing with a common FNB ring
to communicate across the MMAC backplane (i. e., collapsed
backbone configuration), they must have the same FNB ring
number.
- Do not assign duplicate ring numbers to different rings.
• Check the NSRT LED to ensure the TRBMIM-T is logically inserted
into the FNB ring. The bridge cannot pass traffic until it is logically
inserted into the FNB ring. The TRBMIM-T, in the Bridge-Only
mode, will not logically insert into the MMAC backplane under the
following circumstances:
- Its FNB ring speed is different from the ring speed for the FNB
ring into which it is trying to insert.
Make sure the FNB ring speed for the TRBMIM-T is set to run at
the same ring speed as the FNB ring. See Section 2.5.1 for
information on setting the TRBMIM-T FNB ring speed.
- Its FNB ring number does not match the FNB ring number
assigned by a bridge or a router on the FNB ring where the
TRBMIM-T is installed.
- The FNB ring is beaconing.
TRBMIM-T BOOK Page 9 Tuesday, July 2, 1996 10:35 AM