# java.net.UnknownHostException using Java Rest client 5.6.3 **URL:** \ **Category:** Elasticsearch\ **Created:** [November 3, 2017, 3:05pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329 "2017-11-03T15:05:13Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 3, 2017, 3:05pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/1 "2017-11-03T15:05:13Z")
I keep getting java.net.UnknownHostException for connecting to my host elasticsearch. I have not completed the actual search body yet, because I am getting unknown host error. I figure I can solve that problem later. Here is the code, any reason why I cannot reach my cluster? ``` Header[] headers = { new BasicHeader(HttpHeaders.CONTENT_TYPE, "application/json"), new BasicHeader("Role", "Read") }; final CredentialsProvider credentialsProvider = new BasicCredentialsProvider(); credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("user", "password")); RestClient lowLevelRestClient = RestClient.builder( new HttpHost("https://xxxxxxxxx:9243")).setDefaultHeaders(headers).build(); RestHighLevelClient client = new RestHighLevelClient(lowLevelRestClient); String thePath = "index_name"; try { thePath = URLEncoder.encode(thePath, "UTF-8"); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } SearchRequest searchRequest = new SearchRequest(thePath); SearchResponse searchResponse = null; try { searchResponse = client.search(searchRequest); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } ``` ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 3, 2017, 3:45pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/2 "2017-11-03T15:45:05Z")
I believe you should create an http host like this instead: ``` new HttpHost("xxxxxxxxx", 9243, "https") ``` See [https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/\_encrypted\_communication.html](https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/_encrypted_communication.html) ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 3, 2017, 5:06pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/3 "2017-11-03T17:06:13Z")
same error. Any ideas? ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 3, 2017, 5:21pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/4 "2017-11-03T17:21:22Z")
Did you apply everything which is in [https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/\_encrypted\_communication.html](https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/_encrypted_communication.html) ? What are the plugins you are using? Can you share elasticsearch logs? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 3, 2017, 5:53pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/5 "2017-11-03T17:53:13Z")
No, But I am a bit confused. The docs say to instantiate a high level rest object with a low level rest object. Problem is the documentation from your link doesn't use the low level rest client at all. Should I just use what's in your link? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 3, 2017, 6:13pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/6 "2017-11-03T18:13:33Z")
How can I share the logs with you? Is there an export? ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 6, 2017, 6:52am UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/7 "2017-11-06T06:52:38Z")
When you start elasticsearch, it produces logs. Just share them here. Don't forget to format them. > Problem is the documentation from your link doesn't use the low level rest client at all. Isn't that `RestClientBuilder builder = RestClient.builder(...)` a Low Level client? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 7, 2017, 2:35pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/8 "2017-11-07T14:35:27Z")
Here is the doc: > **[Initialization | Java REST Client \[7.17\] | Elastic](https://www.elastic.co/guide/en/elasticsearch/client/java-rest/current/java-rest-high-getting-started-initialization.html)** Also, I am using elastic cloud. My logs appear like this: ![es_cloud_logs](https://us1.discourse-cdn.com/elastic/original/3X/6/3/6356356e960459129b3c0080f823d14d521f3117.jpg) When I click into the logs, there's nothing useful. > "No results found in the last week's logs." ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 9, 2017, 12:09am UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/9 "2017-11-09T00:09:28Z")
Last time I built such a client for elastic cloud service, I wrote: > I did not test it it recently though. Quick question: are you able to do it from the command line using curl for example? I mean are you sure you have the rights to connect to the cluster? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 9, 2017, 4:41pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/10 "2017-11-09T16:41:20Z")
I have not tried CURL. This is what I have now: ``` Header[] headers = { new BasicHeader(HttpHeaders.CONTENT_TYPE, "application/json"), new BasicHeader("Role", "Read") }; final CredentialsProvider credentialsProvider = new BasicCredentialsProvider(); credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials("username", "password")); RestClient r = RestClient.builder(new HttpHost("xxxxxxxxxxxxxx.us-east-1.aws.found.io",9243,"https")).setDefaultHeaders(headers).build(); Map params = Collections.singletonMap("pretty", "true"); Response response = r.performRequest("GET", "/", params); System.out.println(response.toString()); try { r.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } ``` I get the following error: > Exception in thread "main" org.elasticsearch.client.ResponseException: GET [https://xxxxxxxx.us-east-1.aws.found.io:9243/?pretty=true:](https://xxxxxxxx.us-east-1.aws.found.io:9243/?pretty=true:) HTTP/1.1 401 Unauthorized > { > "error" : { > "root\_cause" : [ > { > "type" : "security\_exception", > "reason" : "action [cluster:monitor/main] requires authentication", > "header" : { > "WWW-Authenticate" : "Basic realm="security" charset="UTF-8"" > } > } > ], > "type" : "security\_exception", > "reason" : "action [cluster:monitor/main] requires authentication", > "header" : { > "WWW-Authenticate" : "Basic realm="security" charset="UTF-8"" > } > }, > "status" : 401 > } > > at org.elasticsearch.client.RestClient$1.completed(RestClient.java:354) > at org.elasticsearch.client.RestClient$1.completed(RestClient.java:343) > at org.apache.http.concurrent.BasicFuture.completed(BasicFuture.java:119) > at org.apache.http.impl.nio.client.DefaultClientExchangeHandlerImpl.responseCompleted(DefaultClientExchangeHandlerImpl.java:177) > at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.processResponse(HttpAsyncRequestExecutor.java:436) > at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.inputReady(HttpAsyncRequestExecutor.java:326) > at org.apache.http.impl.nio.DefaultNHttpClientConnection.consumeInput(DefaultNHttpClientConnection.java:265) > at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:81) > at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:39) > at org.apache.http.impl.nio.reactor.AbstractIODispatch.inputReady(AbstractIODispatch.java:121) > at org.apache.http.impl.nio.reactor.BaseIOReactor.readable(BaseIOReactor.java:162) > at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvent(AbstractIOReactor.java:337) > at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvents(AbstractIOReactor.java:315) > at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:276) > at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) > at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:588) > at java.lang.Thread.run(Unknown Source) ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 9, 2017, 5:32pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/11 "2017-11-09T17:32:47Z")
Can you try with curl? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 9, 2017, 5:39pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/12 "2017-11-09T17:39:10Z")
Curls works: `curl -u username:password 'https://xxxxxxxxxxxxxxxxx.us-east-1.aws.found.io:9243/index_name/_search?scroll=1m&size=50&pretty' -d '{"query" : {"match_all" : {}}}'` ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 9, 2017, 6:06pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/13 "2017-11-09T18:06:09Z")
Can you also curl [https://xxxxxxxx.us-east-1.aws.found.io:9243/?pretty=true](https://xxxxxxxx.us-east-1.aws.found.io:9243/?pretty=true) Same user as the ones you put in the rest Client ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 9, 2017, 6:08pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/14 "2017-11-09T18:08:53Z")
Yes, works fine: { "name" : "instance-0000000000", "cluster\_name" : "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx", "cluster\_uuid" : "xxxxxxxxxxxxxxxxxxxxxxxxx", "version" : { "number" : "5.6.3", "build\_hash" : "xxxxxx", "build\_date" : "2017-10-06T20:33:39.012Z", "build\_snapshot" : false, "lucene\_version" : "6.6.1" }, "tagline" : "You Know, for Search" } ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 9, 2017, 7:24pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/15 "2017-11-09T19:24:45Z")
FYI: My Java is run from my desktop. The curl is run from an EC2 instance, ubuntu. ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 9, 2017, 7:36pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/16 "2017-11-09T19:36:43Z")
Can you try from the same platform please? ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 9, 2017, 7:48pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/17 "2017-11-09T19:48:59Z")
Sure, this is what I get: ``` Exception in thread "main" java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58) Caused by: org.elasticsearch.client.ResponseException: GET https://xxxxxxxxxxxx:9243/?pretty=true: HTTP/1.1 401 Unauthorized { "error" : { "root_cause" : [ { "type" : "security_exception", "reason" : "action [cluster:monitor/main] requires authentication", "header" : { "WWW-Authenticate" : "Basic realm=\"security\" charset=\"UTF-8\"" } } ], "type" : "security_exception", "reason" : "action [cluster:monitor/main] requires authentication", "header" : { "WWW-Authenticate" : "Basic realm=\"security\" charset=\"UTF-8\"" } }, "status" : 401 } at org.elasticsearch.client.RestClient$1.completed(RestClient.java:354) at org.elasticsearch.client.RestClient$1.completed(RestClient.java:343) at org.apache.http.concurrent.BasicFuture.completed(BasicFuture.java:119) at org.apache.http.impl.nio.client.DefaultClientExchangeHandlerImpl.responseCompleted(DefaultClientExchangeHandlerImpl.java:177) at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.processResponse(HttpAsyncRequestExecutor.java:436) at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.inputReady(HttpAsyncRequestExecutor.java:326) at org.apache.http.impl.nio.DefaultNHttpClientConnection.consumeInput(DefaultNHttpClientConnection.java:265) at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:81) at org.apache.http.impl.nio.client.InternalIODispatch.onInputReady(InternalIODispatch.java:39) at org.apache.http.impl.nio.reactor.AbstractIODispatch.inputReady(AbstractIODispatch.java:121) at org.apache.http.impl.nio.reactor.BaseIOReactor.readable(BaseIOReactor.java:162) at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvent(AbstractIOReactor.java:337) at org.apache.http.impl.nio.reactor.AbstractIOReactor.processEvents(AbstractIOReactor.java:315) at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:276) at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:588) at java.lang.Thread.run(Thread.java:748) ``` ---
**Author:** ![mc1392](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@mc1392](https://discuss.elastic.co/u/mc1392)\ **Post date:** [November 10, 2017, 11:54am UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/18 "2017-11-10T11:54:47Z")
Problem solved! @dadoonet thanks for the help, again!!! Final issue to solve was my Authorization header. Here is the working code: ``` String encodedBytes = Base64.getEncoder().encodeToString("username:password".getBytes()); Header[] headers = { new BasicHeader(HttpHeaders.CONTENT_TYPE, "application/json"), new BasicHeader("Authorization","Basic "+encodedBytes) }; RestClient r = RestClient .builder(new HttpHost("xxxxxxxxxxx", 9243, "https")) .setDefaultHeaders(headers).build(); Map params = Collections.singletonMap("pretty", "true"); Response response = r.performRequest("GET", "/", params); System.out.println(response.toString()); try { r.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } ``` ---
**Author:** ![dadoonet](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/dadoonet/32/137187_2.png) [@dadoonet](https://discuss.elastic.co/u/dadoonet)\ **Post date:** [November 10, 2017, 12:35pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/19 "2017-11-10T12:35:11Z")
Glad you solved it. I wanted to test it but traveling ATM so hard to do it. 🙂 ---
**Author:** ![system](https://us1.discourse-cdn.com/elastic/original/3X/1/a/1ac57faf039f6b580b3f104ef42a2a89e41014de.png) [@system](https://discuss.elastic.co/u/system)\ **Post date:** [December 8, 2017, 12:35pm UTC](https://discuss.elastic.co/t/java-net-unknownhostexception-using-java-rest-client-5-6-3/106329/20 "2017-12-08T12:35:14Z")
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