Chapter 4 Troubleshooting
Diagnosing Problems
4-4
Catalyst 2950 Desktop Switch Hardware Installation Guide
78-11157-05
Poor performance or
excessive errors
(continued).
Bad adapter in attached device.
•
Excessive errors found in port
statistics.
•
Run adapter card diagnostic
utility.
STP
4
checking for possible loops.
Wait 30 seconds for port status
LED to turn green.
No connectivity.
Incorrect or bad cable.
No link at both ends.
•
A crossover cable was used
when a straight-through was
required, or the reverse.
•
For the correct pinouts and
the proper application of
crossover vs.
straight-through cables, see
the
“Cable and Adapter
Specifications” section on
page B-8
.
•
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 module
documentation for more
information.
Switch not recognizing an SFP
module.
Refer to your SFP module
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 switch software
configuration guide.
Table 4-1
Common Problems and Solutions (continued)
Symptom
Possible Cause
Resolution