Hi. Armbian 21.02.1 / 5.15.74-sunxi (22.08.6 SMP) / Debian 11.5 is working flawlessly on my cubietruck for several days, and then just hangs. I've studied the armbian-hardware-monitor.log, systemlog, run a 2-minute periodic cron to watch the temperature, and even added a serial comsole in an attempt to find out what might be the cause. I have not seen any weird indications in these logs. Temperature stays between 37 and 45 degrees. When the system hangs, there are no error messages on the consoles or via the serial comm. Pings are unresponded then, and magic sysrq won't work then. Armbian is run on a sata harddisk, there are some harddisks attached via an USB hub too but not involved in system-critical tasks. Network is LAN-based.

Can someone recommend what else than desribed above I could do or check to analyze what's going on and leads to the hangup. Thanks in advance.

Serial console is still best chance to get at least something. Make sure to change verbosity to 7 in /boot/armbianEnv.txt and reboot before attempting this again.