Could not validate a connection to Elasticsearch. Unknown 401 error from Elasticsearch null

 curl -X GET 'http://localhost:9200'

{"error":{"root_cause":[{"type":"security_exception","reason":"missing authentication credentials for REST request [/]","header":{"WWW-Authenticate":["Basic realm="security", charset="UTF-8"","ApiKey"]}}],"type":"security_exception","reason":"missing authentication credentials for REST request [/]","header":{"WWW-Authenticate":["Basic realm="security", charset="UTF-8"","ApiKey"]}},"status":401}