Cisco WS-C2950T-48-SI Hardware Installation Manual page 90

Diagnosing Problems
Table 3-1
Symptom
Switch placed in
error-disabled state after
CWDM
module is inserted.
STAT LED on Catalyst 2950
LRE switch is not on.
1. FCS = frame check sequence
2. STP = Spanning Tree Protocol
3. CWDM = Coarse Wave Division Multiplexer
4. CPE = customer premises equipment
Catalyst 2950 Switch Hardware Installation Guide
3-4
Common Problems and Solutions (continued)
Possible Cause
Bad or non-Cisco-approved CWDM
GBIC module or SFP module.
3
GBIC or SFP
Telephone cable is loose or is not
connected properly.
Telephone cable is defective.
Cable trunking defective.
Cisco LRE CPE is not
communicating with
Catalyst 2950 LRE switch, or Cisco
LRE CPE might be attempting to
exceed the rate or the reach selected
by the switch.
Catalyst 2950 LRE switch does not
support the Cisco LRE CPE.
Chapter 3 Troubleshooting
Resolution
Remove the CWDM GBIC or
SFP module from the switch,
and replace it with a
Cisco-approved module. Use the
errdisable recovery cause
gbic-invalid global
configuration command to
verify port status, and enter a
time interval to recover from the
error-disabled state.
See the switch software
configuration guide for
information about the
errdisable recovery command.
Reseat telephone cable into the
telephone wall jack and the
4
Cisco LRE CPE .
Replace the telephone cable.
Repair the cable trunking, or
select an alternative pair of
cables.
Reduce cable length to
•
within the recommended
distances. (See the "LRE
Port" section on page 1-9
for LRE cabling
guidelines.)
See the switch software
•
configuration guide for
information about verifying
LRE port link status.
See the compatibility matrix,
Table 1-1 on page 1-3, for more
information.
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