Diagnosing Problems - Cisco WS-C2950T-48-SI Hardware Installation Manual

Diagnosing Problems

Table 3-1
Symptom
Poor performance or
excessive errors.
Poor performance or
excessive errors
(continued).
Catalyst 2950 Switch Hardware Installation Guide
3-2
Common Problems and Solutions
Possible Cause
Duplex autonegotiation mismatch.
Cabling distance exceeded.
Port statistics show excessive
•
FCS,
alignment errors.
• For 10BASE-T, 100BASE-TX,
and 1000BASE-T connections:
–
–
For GBIC module port
•
connections: The distance
between the GBIC module port
and the attached device exceeds
the GBIC cabling guidelines.
For SFP module port
•
connections: The distance
between the SFP module port
and the attached device exceeds
the SFP cabling guidelines.
Bad adapter in attached device.
• Excessive errors found in port
statistics.
2
STP checking for possible loops.
1
late-collision, or
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.
Chapter 3 Troubleshooting
Resolution
See the switch software
configuration guide for
information about identifying
autonegotiation mismatches.
See 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.
See Table 1-2 on page 1-12
•
for SFP cabling guidelines.
• Run adapter card diagnostic
utility.
Wait 30 seconds for port status
LED to turn green.
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