3com 2948-SFP Plus User Guide

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Table 12 Troubleshooting Solutions  

Device is in a reboot loop  Software fault 

 

Download and install a working or previous software  

 

 

 

 

 

 

 

version from the console.

no connection and the  

Incorrect ethernet cable, 

Check pinout and replace if necessary. 

port lED is off 

 

e.g., crossed rather than 

 

 

 

 

straight cable, or vice 

 

 

 

 

versa, split pair (incorrect 

 

 

 

 

twisting of pairs) 

 

 

 

 

 

 

 

 

 

Fiber optical cable  

Change if necessary. Check Rx and Tx on fiber optic cable. 

 

 

 

 

connection is reversed

 

 

 

 

Bad cable 

 

Replace with a tested cable.

 

 

 

 

Wrong cable type   

Verify that all 10 Mbps connections use a Cat 5 cable.

 

 

 

 

 

 

 

Check the port lED or zoom screen in the nMS 

 

 

 

 

 

 

 

application, and change setting if necessary.

lost Password 

 

 

 

 

Contact 3Com