Cisco Catalyst 2955 Hardware Installation Manual page 192

Diagnosing Problems
.
Table 5-1 Common Problems and Solutions
Symptom
Poor performance or
excessive errors.
Catalyst 2955 Hardware Installation Guide
5-4
Table 5-1 describes how to detect and solve these problems.
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).
• For 100 and 1000 speed
connections:
Wrong cable type (not
–
Cat 5) attached to device
and switch
If the switch is attached to a
–
repeater, the total distance
between the two end
stations exceeds the cabling
guidelines.
Bad adapter in attached device.
Excessive errors found in port
•
statistics.
Spanning Tree Protocol (STP)
checking for possible loops.
Chapter 5 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.
Replace wrong cable type
•
with Cat 5 cable.
See your repeater
•
documentation for cabling
guidelines.
Run adapter card diagnostic
•
utility.
Wait 30 seconds for port status
LED to turn green.
78-14944-03