Hi I have turned on watchdog and configurate them at my raspberry. I tested at my raspberry with fork-bomb and watchdog work - fork-bomb

( I wrote this command to console )
:(){ :|:& };:

freeze my computer and watchdog restart device. But after restart my raspberry pi zero want to write password... Anybody has idea why?

EDIT: I should write that before - if in normal situation I do sudo reboot or restart with, i don't need write login

EDIT2: my watchdog service : /lib/systemd/system/watchdog.service ( i haven't changed it )

Description=watchdog daemon

ExecStartPre=/bin/sh -c '[ -z "${watchdog_module}" ] || [ "${watchdog_module}" = "none" ] || /sbin/modprobe $watchdog_module'
ExecStart=/bin/sh -c '[ $run_watchdog != 1 ] || exec /usr/sbin/watchdog $watchdog_options'
ExecStopPost=/bin/sh -c '[ $run_wd_keepalive != 1 ] || false'

  • Pretty sure that will amount to an unclean shutdown; the forkbomb would have prevented anything else -- I've never used the watchdog, and don't know whether it even tries to do such, but if it does it would fail. While the system wouldn't have been doing much I/O to the SD card at the time, reducing the chance of filesystem corruption, it could still happen.
    – goldilocks
    Jun 11, 2021 at 14:55
  • If you boot normally, do you get asked for a password? Jun 12, 2021 at 1:54
  • @JaromandaX - if i boote normally (for example sudo reboot) after restart i don't need write a password Jun 12, 2021 at 4:38
  • @goldilocks - hmm okay - so if it could be problem with forkbomk what i should use to test of my watchdog work? Jun 12, 2021 at 4:41

2 Answers 2


It is not clear to me what you want to achieve. Do you want that your raspberry reboots without a password prompt / autologin enabled? This can be done in raspi-config 1 System Options--> S5 Boot / Auto Login then select Console Autologin or Desktop Autologin.

  • Exacly - autologin/without a password prompt is my purpose. In normal situation after restart with gui or sudo reboot Normally computer is run and I will be autologged - but when i force raspberry to use watchdog - after restart i need write a pass Jun 12, 2021 at 4:44
  • Can you please post the code of your watchdog?
    – Hannes
    Jun 13, 2021 at 10:57
  • do you mean a watchdog.conf? Jun 14, 2021 at 9:54

Ok i think i found answer at this page (and this worked for fork-bomb case)


I changed in last line from




and ofcourse - i did sudo systemctl daemon-reload in CLI to refresh implement this change to service

Thanks everybody for comments

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