Watchdog on DietPi / RaspberryPi Zero

General Discussion
1

Hello
I tried to activate the watchdog on my system like shown here:

When I start the watchdog service I get the following errors

Jan 08 21:13:14 DietPi systemd[1]: Starting watchdog daemon...
Jan 08 21:13:15 DietPi watchdog[857]: unknown protocol icmp
Jan 08 21:13:15 DietPi sh[857]: watchdog: unknown protocol icmp
Jan 08 21:13:15 DietPi systemd[1]: watchdog.service: Control process exited, code=exited, status=2/INVALIDARGUMENT
Jan 08 21:13:15 DietPi systemd[1]: watchdog.service: Control process exited, code=exited, status=1/FAILURE
Jan 08 21:13:15 DietPi systemd[1]: watchdog.service: Failed with result 'exit-code'.
Jan 08 21:13:15 DietPi systemd[1]: Failed to start watchdog daemon.
Jan 08 21:13:15 DietPi systemd[1]: watchdog.service: Triggering OnFailure= dependencies.

Can you help me?

2

Can you share the service configuration. And maybe you would need to install packages like iputils-ping

3

here’s my configuration:

watchdog.conf.txt (5.9 KB)

iputils-ping was already installed…

4

ping and ping-count are commented in your config :thinking:.

Does this work?

ping 192.168.178.1
5

You are right. The configuration which lead to the errors was this one.
The ping count I did not change (but I tested it also with and without - same result).

watchdog.conf.txt (5.9 KB)

6

Run this and restart watchdog

cat << EOF >> /etc/default/watchdog
watchdog_options="ping"
EOF
systemctl restart watchdog.service
7

This did not change anything. The error message stays the same.

BTW: why are there two configuration files for the watchdog?

8

just executing ping like this:
ping 192.168.178.1

works fine… so very strange why the watchdog cannot execute it…

9

Pls can you share watchdog systemd definition

10

can you tell me how to do this?

11 
systemctl cat watchdog.service
12

That’s strange. I tried to run it on my raspberry and I had the same issue with you. But it was fixed by enabling the ping in the watchdog options.

The defaults is not exactly a configuration file.

13

Here’s the output:

# /lib/systemd/system/watchdog.service
[Unit]
Description=watchdog daemon
Conflicts=wd_keepalive.service
After=multi-user.target
OnFailure=wd_keepalive.service

[Service]
Type=forking
EnvironmentFile=/etc/default/watchdog
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'

[Install]
WantedBy=default.target
14

did a test on RP4B facing the same issue, while it was working fine on a x64 VM. interesting :thinking:

15

Does it probably require logind?

systemctl unmask systemd-logind
apt install dbus
systemctl start systemd-logind

Such a dependency for a watchdog would not be exactly helpful, when e.g. logind hangs (as well), but who knows. systemd added it as dependency for quite a bunch of features with Bookworm (the related systemd version).

16

nope, doesn’t change anything

17

To rule out the systemd unit: when stipping the service, and running watchdog from console with the arguments/options from /etc/default/watchdog, does it work? Ah hence just watchdog ping`.

Ahh wait a second, this cannot work. The watchdog_options are added as arguments just like that according to the systemd unit, and ping is no valid argument @trendy. There is no command-line argument to define the ping method. Instead one can set it e.g. to -c /etc/watchdog.conf to define the config file. That however is the default. So best to keep the watchdog_options variable commented in /etc/default/watchdog.

The command to test one console is hence reallt just watchdog, which then uses mentioned config file, just like the systemd service should do by default.

18 
root@DietPiM6:~# watchdog
watchdog: unknown protocol icmp
root@DietPiM6:~#
19

Okay very weird. I will run some tests when I am back home in a day.