How do I enable remote access/request in Elasticsearch 2.0?

By default http transport and internal elasticsearch transport only listens to localhost. If you want to access Elasticsearch from the host other than localhost then try adding following configurations in config/elasticsearch.yml.

transport.host: localhost 
transport.tcp.port: 9300 
http.port: 9200
network.host: 0.0.0.0

Here, network.host as 0.0.0.0 allow access from any host within the network.

In config/elasticsearch.yml put

network.host: 0.0.0.0