Diagnosing Problems - Cisco Catalyst 3750 Hardware Installation Manual

Chapter 4 Troubleshooting
Table 4-1 Common Problems and Solutions
Symptom
Poor performance or excessive
errors
78-15136-03
Possible Cause
Duplex autonegotiation mismatch.
Cabling distance exceeded
Port statistics show excessive
•
frame check sequence (FCS),
late-collision, or alignment
errors.
For 10/100 and
•
10/100/1000BASE-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.
SFP or XENPAK cabling
•
guidelines exceeded.
Bad adapter in attached device
• Excessive errors found in port
statistics.
• STP checking for possible
loops.
Catalyst 3750 Switch Hardware Installation Guide

Diagnosing Problems

Resolution
Refer to the switch software
configuration guide for
information on identifying
autonegotiation mismatches.
Verify that the autonegotiation
settings are the same at both
ends.
Refer to the switch software
•
configuration guide for
information on displaying
port statistics.
Reduce the cable length to
•
within the recommended
distances.
Refer to your repeater
•
documentation for cabling
guidelines.
Refer to your SFP or
•
XENPAK documentation
for cabling guidelines.
• Run adapter card diagnostic
utility.
• Wait 30 seconds for the port
LED to turn green.
4-5