Cisco WS-C2950-12 Hardware Installation Manual page 97

Chapter 3 Troubleshooting
Table 3-1 Common Problems and Solutions
Symptom
Poor performance or
excessive errors.
78-11157-03
Possible Cause
Duplex autonegotiation mismatch.
Cabling distance exceeded.
Port statistics show excessive
•
frame check sequence (FCS),
late-collision, or alignment
errors.
For 10BASE-T, 100BASE-TX,
•
and 1000BASE-T connections:
The distance between the
–
port and the attached device
exceeds 328 feet
(100 meters).
If the switch is attached to a
–
repeater, the total distance
between the two end
stations exceeds the cabling
guidelines.
For GBIC module port
•
connections: The distance
between the GBIC module port
and the attached device exceeds
the GBIC cabling guidelines.
Bad adapter in attached device.
Excessive errors found in port
•
statistics.
Spanning Tree Protocol (STP)
checking for possible loops.
Catalyst 2950 Desktop Switch Hardware Installation Guide
Diagnosing Problems
Resolution
Refer to the switch software
configuration guide for
information about identifying
autonegotiation mismatches.
Refer to the switch software
•
configuration guide for
information about
displaying port statistics.
Reduce cable length to
•
within the recommended
distances.
Refer to your repeater
•
documentation for cabling
guidelines.
Refer to your GBIC module
•
documentation for cabling
guidelines.
Run adapter card diagnostic
•
utility.
Wait 30 seconds for port status
LED to turn green.
3-3