Not quite sure what to make of this: I'm getting

org.apache.http.NoHttpResponseException: [endpoint_URI]:443 failed to respond

But if I do:

curl https://[endpont_URI]:443

I get a response from Elasticsearch—this is because I have the Amazon Elasticsearch instance permissioned to accept any connections from the IP address where apiman is running.

The apiman configurations look like this:

apiman.es.protocol=http

apiman.es.host=[endpoint_URI]

apiman.es.port=443

apiman.es.username=

apiman.es.password=

Changing protocol from http to https doesn't appear to help, nor does removing the username and password properties entirely. Any suggestions?