Technical Tip: Kernel Error in FortiGate and how to recover

[nevan]

Description	This article describes what can cause a kernel error incident in the FortiGate and the best way to handle them
Scope	FortiGate.
Solution	The kernel is the core component that creates the bridge between hardware and software. In general, it handles the low-level tasks related to the management of disk or memory and processing of network traffic. Issues can arise which cause the kernel to 'halt' or 'panic.  At that point, the FortiGate is no longer able to operate and manual intervention is generally needed.  Before attempting any of the below, it is always best to get a console connection to the FortiGate so the kernel panic log can be captured. This would be required for TAC to pinpoint specifically what had caused that kernel panic to occur. More details are visible here: Troubleshooting Tip: How to deal with a kernel panic Reboot: A simple reboot will return the FortiGate back to a working state. Depending on what the specific trigger of the kernel panic was, it may occur again. Check resources: There may be historical data indicating that the FortiGate was starved for resources leading up to the kernel panic.  This can be seen by navigating to Log & Report > System Events > General System Events, and filtering the 'Log Description' to 'System performance statistics'. See more details here: https://community.fortinet.com/t5/FortiGate/Technical-Tip-Performance-statistics-logs/ta-p/198402 Inspect hardware: If the problem persists, there could be a hardware issue. It may be possible to run an HQIP test to diagnose the failure. See this article for more details: Technical Tip: RMA: HQIP test (with built-in FortiOS diagnostic commands) These steps can be followed if the Kernel error incident is being observed in both running, newly installed OS version while implementing a new operating system or OS upgrade. Additional information:  If the following errors 'Kernel panic - not syncing: Fatal exception' or 'kernel error: unable to handle kernel NULL pointer dereference.. appear in the recent release of v7.4.4, and if they are not resolved with a reboot, contact the Fortinet Technical Assistance Center https://support.fortinet.com regarding the error. Related articles: Troubleshooting Tip: How to deal with a kernel panic Technical Tip: simulating a kernel crash in FGVM