title: Unknown host exception while using Java APIs to index documents (RestHighLevelClient) Elasticsearch
body: <p>I am using the vpc endpoint for elastic search to index my documents using RestHighLevelClient.</p>
  
  <p>I am using java high level rest client v6.2.2 to connect Elasticsearch version 6.0 </p>
  
  <p>I am able to access my cluster endpoint without the need of any authentication - <a href="https://vpc......us-east-1.es.amazonaws.com" rel="nofollow noreferrer">https://vpc......us-east-1.es.amazonaws.com</a></p>
  
  <p>Code is as below:</p>
  
  <pre><code>          RestHighLevelClient client = null;
  
          try {
              Header[] headers = { new BasicHeader(HttpHeaders.CONTENT_TYPE, "application/json")};
  
              RestClientBuilder restClientBuilder = RestClient.builder(new HttpHost("https://vpc...us-east-1.es.amazonaws.com", 9200, "https"));
              restClientBuilder.setMaxRetryTimeoutMillis(30); //Currently, set as default
              restClientBuilder.setDefaultHeaders(headers);
  
              client = new RestHighLevelClient(restClientBuilder);
  
              IndexRequest indexRequest = new IndexRequest(index, "doc", 1)
                      .source(documentJson, XContentType.JSON);
  
  
              indexRequest.setRefreshPolicy(WriteRequest.RefreshPolicy.IMMEDIATE);
  
              IndexResponse indexResponse = client.index(indexRequest);
  
          }catch(Exception e){
  
          }finally {
              try {
                  client.close();
              } catch (IOException e) {
  
              }
          }
      }
  </code></pre>
  
  <p>Exception: </p>
  
  <pre><code>Caused by: java.net.UnknownHostException: https://vpc-had-webapps-logs-umrm7skxqc2n5z6wc5jx632que.us-east-1.es.amazonaws.com/
      at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method) ~[na:1.8.0_45]
      at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:907) ~[na:1.8.0_45]
      at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1302) ~[na:1.8.0_45]
      at java.net.InetAddress.getAllByName0(InetAddress.java:1255) ~[na:1.8.0_45]
      at java.net.InetAddress.getAllByName(InetAddress.java:1171) ~[na:1.8.0_45]
      at java.net.InetAddress.getAllByName(InetAddress.java:1105) ~[na:1.8.0_45]
      at org.apache.http.impl.conn.SystemDefaultDnsResolver.resolve(SystemDefaultDnsResolver.java:45) ~[httpclient-4.5.5.jar:4.5.5]
      at org.apache.http.impl.nio.conn.PoolingNHttpClientConnectionManager$InternalAddressResolver.resolveRemoteAddress(PoolingNHttpClientConnectionManager.java:637) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.apache.http.impl.nio.conn.PoolingNHttpClientConnectionManager$InternalAddressResolver.resolveRemoteAddress(PoolingNHttpClientConnectionManager.java:608) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.apache.http.nio.pool.AbstractNIOConnPool.processPendingRequest(AbstractNIOConnPool.java:474) ~[httpcore-nio-4.4.9.jar:4.4.9]
      at org.apache.http.nio.pool.AbstractNIOConnPool.lease(AbstractNIOConnPool.java:280) ~[httpcore-nio-4.4.9.jar:4.4.9]
      at org.apache.http.impl.nio.conn.PoolingNHttpClientConnectionManager.requestConnection(PoolingNHttpClientConnectionManager.java:268) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.apache.http.impl.nio.client.AbstractClientExchangeHandler.requestConnection(AbstractClientExchangeHandler.java:377) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.apache.http.impl.nio.client.DefaultClientExchangeHandlerImpl.start(DefaultClientExchangeHandlerImpl.java:129) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.apache.http.impl.nio.client.InternalHttpAsyncClient.execute(InternalHttpAsyncClient.java:141) ~[httpasyncclient-4.1.3.jar:4.1.3]
      at org.elasticsearch.client.RestClient.performRequestAsync(RestClient.java:346) ~[elasticsearch-rest-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestClient.performRequestAsync(RestClient.java:328) ~[elasticsearch-rest-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestClient.performRequest(RestClient.java:221) ~[elasticsearch-rest-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestClient.performRequest(RestClient.java:194) ~[elasticsearch-rest-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:488) ~[elasticsearch-rest-high-level-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:474) ~[elasticsearch-rest-high-level-client-6.2.2.jar:5.6.8]
      at org.elasticsearch.client.RestHighLevelClient.index(RestHighLevelClient.java:335) ~[elasticsearch-rest-high-level-client-6.2.2.jar:5.6.8]
  </code></pre>
  
  <p>Appreciate any inputs. 
  thanks!</p>