Check REST API
export ENDPOINT=localhost:9200
curl -X GET "$ENDPOINT/_cluster/health?wait_for_status=yellow&timeout=50s&pretty"
curl -X GET "$ENDPOINT/_cluster/stats?human&pretty"
curl -X GET "$ENDPOINT/_cluster/pending_tasks"
curl -X GET "$ENDPOINT/_nodes"
curl -X GET "$ENDPOINT/_nodes/stats"
curl -X GET "$ENDPOINT/_cluster/settings?include_defaults=true&flat_settings=true"