Chapter5 Troubleshooting
Diagnosing Problems
5-4
Catalyst 2955 Hardware Installation Guide
78-14944-03
Table 5-1 describes how to detect and solve these problems.
.
Table 5-1 Common Problems and Solutions
Symptom Possible Cause Resolution
Poor performance or
excessive errors.
Duplex autonegotiation mismatch. See the switch software
configuration guide for
information about identifying
autonegotiation mismatches.
Cabling distance exceeded.
• Port statistics show excessive
frame check sequence (FCS),
late-collision, or alignment
errors.
• See the switch software
configuration guide for
information about
displaying port statistics.
• For 10BASE-T, 100BASE-TX,
and 1000BASE-T connections:
–
The distance between the
port and the attached device
exceeds 328 feet
(100 meters).
• Reduce cable length to
within the recommended
distances.
• For 100 and 1000 speed
connections:
–
Wrong cable type (not
Cat 5) attached to device
and switch
• Replace wrong cable type
with Cat 5 cable.
–
If the switch is attached to a
repeater, the total distance
between the two end
stations exceeds the cabling
guidelines.
• See your repeater
documentation for cabling
guidelines.
Bad adapter in attached device.
• Excessive errors found in port
statistics.
• Run adapter card diagnostic
utility.
Spanning Tree Protocol (STP)
checking for possible loops.
Wait 30 seconds for port status
LED to turn green.
