Solution To Device Login Failure - Huawei S1720 Series Quick Maintenance Manual

Solution to Device Login Failure

If you fail to log in to the switch through Telnet or STelnet, log in to the switch through the Console (also
called serial) port and check the Telnet or STelnet configuration.
If you still fail to log in to the switch through the Console port, you cannot perform any operations related
to CLI. In this situation, you need to perform the following operations:
Perform the following operations only when you confirm that the user
service has been interrupted, because these operations will affect user
service. Collect the fault information and contact your agent or Huawei
enterprise technical support hotline.
Check and recover the power supply system.
1
If all indicators on the switch are off and the fans do not work (listening to the noise), the power supply
system fails.
1.Check the power supply switches. If your switch has multiple power supplies installed, at least one
power supply must be switched on.
2.Check the Input or STATUS indicator of the power supply. If the indicator is off, the power supply
input is abnormal. Request the electrician to recover the power lines in the equipment room, rack, or
cabinet.
3.Check the Output indicator of the power supply. If the indicator is off, the power supply is abnormal.
Replace the power supply.
4.If the switch cannot be powered on and no error is found in the preceding checks, contact your
agent or Huawei enterprise technical support hotline.
2
Check and modify the communication parameters of the COM port on your computer.
Check whether the communication parameters of the COM port are the same as the those of the
switch's Console port. If not, modify the communication parameters.
The default settings of the switch's Console port parameters include 9600 bps, 8 data bits, 1 stop bit,
no parity check, and no flow control (the actual settings may be different).
Restart the switch.
3
Power off the switch, and then power on it.
4
Seek technical support.
If the preceding methods are ineffective, contact your agent or Huawei enterprise technical support
hotline.
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