Raspberry Pi OS • watchdog on 64 bit bookworm.

Please can anyone tell me how to use the watchdog on 64 bit bookworm lite?

My watchdog.service keeps saying it can't access /dev/watchdog

Also, some people say the configuration of what I want watched goes in /etc/watchdog.conf while others seem to be saying it has been simplified and moved to /etc/systemd/system.conf. Which is it?

I can't get beyond sudo systemctl status watchdog.service saying:

watchdog.service - watchdog daemon
Loaded: loaded (/lib/systemd/system/watchdog.service; enabled; preset: enabled)
Active: active (running) since Thu 2024-01-04 01:41:11 GMT; 24min ago
Process: 1580 ExecStartPre=/bin/sh -c [ -z "${watchdog_module}" ] || [ "${watchdog_module}" = "none" ] || /sbin/modprobe $watchdog_module (code=exited, status=0/SUCCESS)
Process: 1581 ExecStart=/bin/sh -c [ $run_watchdog != 1 ] || exec /usr/sbin/watchdog $watchdog_options (code=exited, status=0/SUCCESS)
Main PID: 1583 (watchdog)
Tasks: 1 (limit: 457)
CPU: 339ms
CGroup: /system.slice/watchdog.service
└─1583 /usr/sbin/watchdog

Jan 04 01:41:11 pi-server watchdog[1583]: pidfile: /var/run/nginx.pid
Jan 04 01:41:11 pi-server watchdog[1583]: interface: no interface to check
Jan 04 01:41:11 pi-server watchdog[1583]: temperature: no sensors to check
Jan 04 01:41:11 pi-server watchdog[1583]: no test binary files
Jan 04 01:41:11 pi-server watchdog[1583]: no repair binary files
Jan 04 01:41:11 pi-server watchdog[1583]: error retry time-out = 60 seconds
Jan 04 01:41:11 pi-server watchdog[1583]: repair attempts = 1
Jan 04 01:41:11 pi-server watchdog[1583]: alive=/dev/watchdog heartbeat=[none] to=root no_act=no force=no
Jan 04 01:41:11 pi-server watchdog[1583]: cannot open /dev/watchdog (errno = 16 = 'Device or resource busy')
Jan 04 01:41:11 pi-server systemd[1]: Started watchdog.service - watchdog daemon.

Statistics: Posted by BrianG61UK — Thu Jan 04, 2024 2:13 am

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