Chapter3      Troubleshooting
Understanding POST Results
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Catalyst 2950 Desktop Switch Hardware Installation Guide
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Understanding POST Results
While the switch powers on, it automatically begins POST, a series of tests that 
verifies that the switch functions properly. When the switch begins POST, the 
system LED is off. If POST completes successfully, the LED turns green. If POST 
fails, the LED turns amber.
Note POST failures are usually fatal. Call Cisco Systems if your switch does not 
pass POST.
Diagnosing Problems
Common switch problems fall into these categories:
• Poor performance
• No connectivity
• Corrupted software
Table 3-1 describes how to detect and solve these problems.