This post is older than a year. Consider some information might not be accurate anymore.
This small shell script checks if an Elasticsearch instance is running by querying the REST API.
#!/usr/bin/env bash
PORT=9200
URL="http://localhost:$PORT"
# Check that Elasticsearch is running
curl -s $URL 2>&1 > /dev/null
if [ $? != 0 ]; then
echo "Unable to contact Elasticsearch on port $PORT."
echo "Please ensure Elasticsearch is running and can be reached at $URL"
exit -1
fi