nginx send blank 200 responses

Solution 1:

HTTP status code 204 No Content is meant to say "I've completed the request, but there is no body to return":

10.2.5 204 No Content

The server has fulfilled the request but does not need to return an entity-body, and might want to return updated metainformation. The response MAY include new or updated metainformation in the form of entity-headers, which if present SHOULD be associated with the requested variant.

If the client is a user agent, it SHOULD NOT change its document view from that which caused the request to be sent. This response is primarily intended to allow input for actions to take place without causing a change to the user agent's active document view, although any new or updated metainformation SHOULD be applied to the document currently in the user agent's active view.

The 204 response MUST NOT include a message-body, and thus is always terminated by the first empty line after the header fields.

Solution 2:

You can have nginx return back an empty HTTP 200 by a config block like:

location = /health {
  return 200;
  #access_log off;
}

You can uncomment the access_log line if you dont want all those health checks to be logged.