How to monitor Elasticsearch?

I can't see any way to monitor Elasticsearch network traffic with Packetbeat. Is this possible?

I don't mean the ES instance that logstash uses, but other instances in our application. It seems like the most obvious use case to me, and I may just be lissing something obvious. It is monitorable by another beat somewhere?

you mean the HTTP used by elasticsearch? If plain HTTP is used, it can be monitored by packetbeat. But you will need logstash to parse the URL and json content. Somewhat related to REST interfaces support:

Thanks, I'll look into that.