No output occurs on the console

On the console terminal, no log isdisplayed or only part of logs are displayed when you type characters.

The switch may properly work or abnormallyforward packets (for example, the network under the switch is interrupted).

Possible Causes

1) Console setting errors (baud rate, flowcontrol, and COM port) on the host

2) Console cable damage

3) PC system faults

4) Switch software faults, causing processcrash

5) Switch hardware faults (forexample, faults of stacking modules or cables causing switch crash, and faultsof console-based circuit)

Troubleshooting ProcedureStep1: Check whether flow control is disabled on theterminal management software (SecureCRT or Hyper Terminal).

If the setting is incorrect, correct andsaved it, exit and the restart the software. Flow control is enabled by defaulton the SecureCRT. Disable flow control when setting parameters.

                              

Flow control is disabled on the HyperTerminal by default. If it is enabled, reset its default setting.

Step2: Check whether the COM port is correct.

Right-click My Computer and then choose DeviceManager > Ports (COM & LPT).

The COM port needs to be the same as theserial port specified on the Hyper Terminal or SecureCRT.

Step3: Change the baud rate to 57600 or 115200 to checkwhether the fault is rectified. The default baud rate is 9600 on the consoleport.

If the fault persists, go to Step 4.

Step4: Press Ctrl+Shift+6 and then enter x to checkwhether the console port is recovered.Step5: Check whether the device can be accessed throughTelnet and check with the customer about whether services are operational.

If services are operational and the devicesupports Telnet, run the following commands under Telnet (no risk) to identifythe cause for no output on the console terminal:

Ruijie#debugsu

Ruijie(support)#tech-supportpackage

After information collection, run the clear line console 0 command to recoverservices. If the services are not recovered, collect information and contactRuijie technical support.

If services are operational but the devicecannot be accessed through Telnet, run the following commands to identify thecause for no output on the console terminal:

Collection poses highrisks (@@@@@ may even cause network interruption). Before performing thefollowing operations, clarify the risks with the customer and collectinformation when no service or service risk is available.

Connect the faulty device to the consoleport.

Run the following commands in sequence. Ifthe customer wants to recover services, restart the switch whether thecollection is complete or not. (4Esc indicates pressing the Esc button for fourtimes.)

4Esc +b           : reboot

4Esc +d           : debug_show_all_locks

4Esc +c           : open and close console

4Esc +f           : dump tech-support info

4Esc +h           : help

4Esc +i           : dump cli debug info

4Esc +j           : dump irq info

4Esc +k + pid + #  : kill pid proc

4Esc +l           : dump start process

4Esc +m           : dump mem info

4Esc +n           : start hrtimer

4Esc +o           : stop hrtimer

4Esc +p           : close logging message(sameas: no logging on)

4Esc +q           : dump context switches andruntime

4Esc +r           : dump other cpu dump_stack

4Esc +s           : show 5@ info

4Esc +t           : show task states

4Esc +x           : start dot task

4Esc +y           : stop dot task

If the devices are in a VSU system, run thefollowing commands on each standby device:

@@@@C

Ruijie#debugsu   

Ruijie(support)#tech-supportpackage

After information collection, submit casesto the service portal for further troubleshooting.