Error at the end of flush

[howardyoo]

May 13, 2020 9:53:26 AM com.wavefront.sdk.direct.ingestion.WavefrontDirectIngestionClient internalFlush
WARNING: Error reporting points, respStatus=406
May 13, 2020 9:56:25 AM com.wavefront.sdk.direct.ingestion.WavefrontDirectIngestionClient close
WARNING: error flushing buffer
java.io.IOException: attempt to flush closed sender
	at com.wavefront.sdk.direct.ingestion.WavefrontDirectIngestionClient.flush(WavefrontDirectIngestionClient.java:357)
	at com.wavefront.sdk.direct.ingestion.WavefrontDirectIngestionClient.close(WavefrontDirectIngestionClient.java:424)
	at com.vmware.vropsexport.processors.WavefrontPusher.close(WavefrontPusher.java:96)
	at com.vmware.vropsexport.Exporter.exportTo(Exporter.java:217)
	at com.vmware.vropsexport.Main.main(Main.java:184)

I'm not sure why this is happening, but this happens everytime I try to run the exporter, in direct ingestion mode. Also, I randomly see 406 errors (which may not be related to the exporter itself), but want to know why that's happening in more details.

[howardyoo]

Maybe it's okay, since the message is WARNING..? I do see the data being populated, but now as I see these messages, I'm not sure whether all the data are being transmitted successfully.