Couldn't bulk index - Unable to flush message buffer

Graylog Central (peer support)
2

Hello,

I looked over you logs. I didn’t notice any “connection” issues, mainly bulk request issues.

ERROR: org.graylog2.indexer.messages.Messages - Couldn't bulk index 1000 messages.

What is your Heap for Elasticsearch?

 ERROR: org.graylog2.outputs.BlockingBatchedESOutput - Unable to flush message buffer

Maybe the answer can be found here.

Insure elasticsearch is working correctly.
Perhaps this site might help