Why is collectd service is not sending data to splunk on Ubuntu 16?

[ad077]

collectd service is not sending data to splunk on Ubuntu 16.

Jan 28 08:07:10 cga2ubctd systemd[1]: Starting Statistics collection and monitoring daemon...
Jan 28 08:07:10 cga2ubctd collectd[18237]: Ignoring unknown LoadPlugin option "FlushInterval" for plugin "write_splunk"
Jan 28 08:07:10 cga2ubctd collectd[18240]: Ignoring unknown LoadPlugin option "FlushInterval" for plugin "write_splunk"
Jan 28 08:07:10 cga2ubctd collectd[18240]: supervised by systemd, will signal readyness
Jan 28 08:07:10 cga2ubctd systemd[1]: Started Statistics collection and monitoring daemon.

any idea?

[bgraabek_splunk]

The write_splunk plugin is not a standard collectd plugin so if you've installed the standard collectd package for Ubuntu 16 you won't have that plugin and hence you might see the error message about an unknown plugin option. At least this is my guess.
There are many ways to collect (no pun intended) collectd data and the write_splunk plugin is only one of them.
If the write_splunk plugin is what you want to use, you will need to get it from a Splunk instance that has the Splunk App for Infrastructure (link text) installed. If you do install that, it can create a CLI script that will install and configure collectd for you.
Alternatively I would suggest you look at the answer to this question as it has several links to more inforation that might provide the answer you need:
link text
If you are using the standard collectd package, one of the ways to collect data is using write_http, however as I recall the collectd package that came with Ubuntu 16 is too old to have the write_http plugin.