With the previous way systemd services were exported, you had to enable every single process one by one to get the service operational.
Consider the following Procfile:
web: bundle exec thin start
worker: bundle exec worker start
Exported with:
foreman export systemd /usr/lib/systemd/system -a myapp -c worker=3
You will have to perform the following to start the service:
systemctl enable myapp-web-1.service
systemctl enable myapp-worker-1.service
systemctl enable myapp-worker-2.service
systemctl enable myapp-worker-3.service
systemctl enable myapp-web.target
systemctl enable myapp-worker.target
systemctl start myapp.target
Thats 7 commands, and you have to know the names of each service. Nasty.
With the changes here, you will have to perform the following:
systemctl enable myapp.target
systemctl start myapp.target
You can also `systemctl start myapp.target` without enabling as well. Previously if you tried to start `myapp.target` without enabling each individual process it would not work.
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Additionally, this change also adds the dependency to 'multi-user.target' (the default behavior for all services). This will properly shut down (or start) the app when the system changes runlevels. The previous method did not do this.
http://0pointer.de/blog/projects/systemd.html
This adds support for exporting systemd targets and services. The
structure is based on the existing upstart support.
Quality is draft and expected to refine in the coming weeks.
One Foremanism that is not respected by these export templates is the
usual log output location, instead stdout and stderr go to syslog.