I am trying to enable the watchdog service (on Raspbian Jessie).

I have installed watchdog and (hopefully) configured it.
sudo systemctl start watchdog seems to start it OK

systemctl status watchdog.service shows it running:-

● watchdog.service - watchdog daemon
 Loaded: loaded (/lib/systemd/system/watchdog.service; static)
 Active: active (running) since Mon 2017-02-20 15:52:46 AEDT; 22s ago
 Process: 1828 ExecStart=/bin/sh -c [ $run_watchdog != 1 ] || exec /usr/sbin/watchdog $watchdog_options (code=exited, status=0/SUCCESS)
 Process: 1824 ExecStartPre=/bin/sh -c [ -z "$watchdog_module" ] || [ "$watchdog_module" = "none" ] || /sbin/modprobe $watchdog_module (code=exited, status=0/SUCCESS)
 Main PID: 1831 (watchdog)
 CGroup: /system.slice/watchdog.service
 └─1831 /usr/sbin/watchdog

When I try to enable it with sudo systemctl enable watchdog I get this strange output

Synchronizing state for watchdog.service with sysvinit using update-rc.d...
Executing /usr/sbin/update-rc.d watchdog defaults
Executing /usr/sbin/update-rc.d watchdog enable
The unit files have no [Install] section. They are not meant to be enabled
using systemctl.
Possible reasons for having this kind of units are:
1) A unit may be statically enabled by being symlinked from another unit's
 .wants/ or .requires/ directory.
2) A unit's purpose may be to act as a helper for some other unit which has
 a requirement dependency on it.
3) A unit may be started when needed via activation (socket, path, timer,
 D-Bus, udev, scripted systemctl call, ...).

Trying sudo update-rc.d watchdog enable did not seem to be successful either
systemctl list-units | grep watchdog

cat /lib/systemd/system/watchdog.service indeed has no [Install] section

[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]

How can I debug this, and get watchdog to run on boot

I added the following to /lib/systemd/system/watchdog.service

[Install]
WantedBy=multi-user.target

watchdog now starts. I will need to test to ensure that it works!

This is a known Debian bug. The systemd integration of the Debian watchdog package has gone through several rounds, varying quite wildly. The watchdog package that went out as Debian 8 was actually non-functional, as you have discovered. That wasn't picked up by pre-release testing.

The bug has been fixed for version 5.15-1 of the package, alongside another fix that corrects faulty service unit syntax (also visible in your service unit). This version is not available in Debian 8 backports, although two requests have been made (and apparently ignored) for it to be.

Further reading

• Paul Menzel (2016-09-19). Syntax error in systemd service file. Bug #838305. Debian bug tracker.


• Uwe Storbeck (2014-11-05). watchdog does not start at boot. Bug #768168. Debian bug tracker.


• Andreas Steinel (2015-07-22). Not starting automatically on freshly installed Jessie. Bug #793309. Debian bug tracker.


• Michael Meskes (2016-02-26). Accepted watchdog 5.15-1 (source amd64) into unstable. debian-devel-changes.

For armbian, you can install updated package manually:

wget http://ftp.debian.org/debian/pool/main/w/watchdog/watchdog_5.15-2_armhf.deb
dpkg -i watchdog_5.15-2_armhf.deb
systemctl enable watchdog