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Troubleshooting Unexpected Reboots

Unexpected reboots are caused by one of two things – hardware problems, or FreeBSD kernel panics. The vast majority of the time, it is hardware problems. Hardware diagnostics should be run before trying anything else.

If the reboot was caused by a kernel panic, the firewall has swap space available, a prompt will be shown when logging back into the web interface asking to view and submit a crash report. If there is no kernel panic, then the cause is almost certainly a hardware problem.

For hardware issues, check on:

  • Failing power supply

  • Flaky electricity in general

  • Overheating CPU

  • Overheating or bad RAM

  • Faulty hard drive/SSD/other storage

  • Faulty drive cables

  • and many others…

If the firewall does panic, and the panic message contains a backtrace that mentions things like memory allocation, mbuf, uma_zalloc_arg, or similar, then it may be crashing due to mbuf exhaustion. See Tuning and Troubleshooting Network Cards for information on how to overcome that problem.

On systems without swap space, an automatic crash dump will not happen. The details of the crash and backtrace would need to be viewed on the console if possible.