3Com 2924-SFP User Manual page 193

Table 12 Troubleshooting Solutions
Problems
Switch does not run; power
LED is off.
Cannot connect to
management using
Console connection
Cannot connect to switch
management using HTTP,
SNMP, etc.
No response from the
terminal emulation
software
Response from the terminal
emulations software is not
readable
Self-test exceeds 15
seconds
No connection is
established and the port
LED is on
Possible Cause
Power is disconnected.
Faulty serial cable
Incorrect serial cable
Software settings
Faulty serial cable
Software settings
The device may not be
correctly installed.
Wrong network address in
the workstation
No network address set
Wrong or missing protocol
Faulty ethernet cable
Faulty port
Faulty module
Incorrect initial
configuration
Solution
Verify that the power cord is properly connected to the
switch, and to the mains supply.
Be sure the terminal emulator program is set to VT-100
compatible, 38400 baud rate, no parity, 8 data bits and
one stop bit
Use the included cable, or be sure that the pin-out
complies with a standard null-modem cable
Be sure the switch has a valid IP address, subnet mask and
default gateway configured
Check that your cable is properly connected with a valid
link light, and that the port has not been disabled
Ensure that your management station is plugged into the
appropriate VLAN to manage the device
If you cannot connect using the web, the maximum
number of connections may already be open. Please try
again at a later time.
Replace the serial cable
Replace serial cable for a pin-to-pin straight/flat cable
Reconfigure the emulation software connection settings.
Replace the serial cable
Reconfigure the emulation software connection settings.
Remove and reinstall the device. If that does not help,
consult your technical support representative.
Configure the network address in the workstation
Configure the network address in the workstation
Configure the workstation with IP protocol
Replace the cable
Replace the module
Replace the module
Erase the connection and reconfigure the port
Troubleshooting Solutions 193