Chapter 3 Troubleshooting
Diagnosing Problems
3-4
Catalyst 2950 Desktop Switch Hardware Installation Guide
78-11157-02
No connectivity.
Incorrect or bad cable.
No link at both ends.
•
A crossover cable was used
when a straight-through was
required, or vice-versa.
•
For the correct pinouts and
the proper application of
crossover vs.
straight-through cables, see
the
Specifications” section on
page B-6
•
The cable is wired incorrectly.
•
Replace it with a tested
good cable.
•
STP checking for possible
loops.
•
Wait 30 seconds for port
status LED to turn green.
Switch not recognizing a GBIC
module.
Refer to your GBIC
documentation for more
information.
Unreadable characters on
the management console.
Incorrect baud rate.
Reset the terminal-emulation
software to 9600 baud.
System LED is amber, and
all port LEDs are off.
Corrupted software.
Attach a monitor to the serial
port to display the switch boot
loader. For more information,
refer to the Catalyst 2950
Desktop Switch Software
Configuration Guide.
System LED is amber
•
Internal fan fault detected.
•
Check if the fan has failed
by using the show env fan
privileged EXEC command.
If the fan has failed, call
Cisco Systems.
•
Nonfatal or fatal POST error
detected.
•
Use the show post
privileged EXEC command
to see which POST test
failed.
Table 3-1
Common Problems and Solutions (continued)
Symptom
Possible Cause
Resolution
