Random commands

List disks

lsblk

pgrep - List child processes of a parent

pgrep -P PID_OF_PARENT

last reboot

See information in /var/log/wtmp about the last reboots.

turn off the backlight

This won’t work everywhere, but might be a clue for those situations.

echo "0" > /sys/class/backlight/intel_backlight/brightness

lidswitch logind.conf

edit /etc/systemd/logind.conf to turn off stuff that happens when the lid is closed on a laptop.

HandleLidSwitch=ignore
HandleListSwitchExternalPower=ignore
HandleLidSwitch=Docker=ignore