Troubleshooting Solutions - 3Com 3CRUS2475 User Manual

Problems
Cannot connect to
management using
RS-232 serial connection
Cannot connect to
switch management
using Telnet, 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
Device is in a reboot loop
Possible Cause
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
Software fault
Solution
Be sure the terminal emulator program is set to VT-100
compatible, 9600 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 Telnet or 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
Download and install a working or previous software
version from the console

Troubleshooting Solutions

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