How to debug an unexpected reboot issue on the USG Flex H model?

Zyxel_Jeff

Question :

How to debug an unexpected reboot issue on the USG FLEX H model?

Answer :

The firewall device may experience unexpected reboots due to unknown reasons. To troubleshoot this issue, please follow the steps below:

Step 1:
Prepare a PC and connect it to the USG Flex H firewall using a console cable.
Access the CLI and enter the following command to enable kernel-level logging:

usgflex500h> cmd debug kernel console-level 8  
OK.

This will activate console-level 8 logging. Please keep the console log running and continue collecting logs.

Step 2:
Wait for the device to experience the unexpected reboot.

Step 3:
After the reboot, navigate to:
Maintenance > Diagnostics > Diagnostics
Then click "Collect Now" to gather the diagnostic log (diag-info).

Step 4:
Please provide both the collected console log and the diagnostic log files to the Zyxel Support Team for further investigation.