Kibana4.1.1 incompatile with ES-2.1.1

when ES use default config, kibana start print the following error:
{"name":"Kibana","hostname":"ubuntu","pid":14260,"level":60,"err":{"message":"unknown error","name":"Error","stack":"Error: unknown error\n at respond (/opt/kibana/src/node_modules/elasticsearch/src/lib/transport.js:237:15)\n at checkRespForFailure (/opt/kibana/src/node_modules/elasticsearch/src/lib/transport.js:203:7)\n at HttpConnector. (/opt/kibana/src/node_modules/elasticsearch/src/lib/connectors/http.js:156:7)\n at IncomingMessage.bound (/opt/kibana/src/node_modules/elasticsearch/node_modules/lodash-node/modern/internals/baseBind.js:56:17)\n at IncomingMessage.emit (events.js:117:20)\n at _stream_readable.js:944:16\n at process._tickCallback (node.js:448:13)"},"msg":"","time":"2016-02-02T13:11:19.598Z","v":0}.
I debug with node-inspector, find kibana use client.ping to test whether ES is alive.(HEAD http://localhost:9200).
But ES-2.1.1 respond HEAD with empty string "".

That is correct, Kibana 4.1 does not support Elasticsearch 2. If you want to use Elasticsearch 2.1, you'll need to use Kibana 4.3.

See the support matrix for more detail: https://www.elastic.co/support/matrix#show_compatibility