fix telegraf service

[zbindenren]

There has been a change in systemd service to start telegraf which does not work anymore with the KillMode=process setting.

If you keep that KillMode, a stop just kills the bash, but keeps telegraf service. With that setting, it is possible to run serveral telegraf instances.

With the old setting:

$ systemctl start telegraf

you see following process:

/bin/sh -c /usr/bin/telegraf -config /etc/telegraf/telegraf.conf -config-directory /etc/telegraf/telegraf.d  >>/var/log/telegraf/telegraf.log 2>>/var/log/telegraf/telegraf.log

Then with:

$ systemctl stop telegraf

the service is still running.

/usr/bin/telegraf -config /etc/telegraf/telegraf.conf -config-directory /etc/telegraf/telegraf.d

Only the parent bash got killed. If you start telegraf with sytemd again, the service runs twice.

This Pull Request fixes that issue.

Required for all PRs:

• CHANGELOG.md updated
• Sign CLA (if not already signed)
• README.md updated (if adding a new plugin)

[sparrc]

InfluxDB uses KillMode=control-group, would this work for telegraf?

[zbindenren]

That is the default value, that is why I removed the entry.

[sparrc]

please leave it explicitly for consistency

[zbindenren]

Ok, I change the pull request.

[sparrc]

also please update the changelog and I will merge, thank you!

[zbindenren]

Changelog and service updated.