使用 Rest 高级客户端检索数据或将数据插入 Elastic Search 时出现 SocketTimeoutException
SocketTimeoutException while retrieving or inserting data into Elastic Search by using Rest High Level Client
我面对 SocketTimeoutException 而 retrieving/inserting 数据 from/to 弹性。当大约 10-30 request/second 时就会发生这种情况。这些请求是 get/put.
的组合
这是我的弹性配置：
3 master nodes 每个 4GB RAM2 data nodes 每个 8GM RAM- 连接到上述数据节点的 Azure 负载均衡器（似乎只打开了 9200 端口）。 java 客户端连接到此负载均衡器，因为它只公开。
- 弹性版本：7.2.0
其余高级客户：
<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.2.0</version>
</dependency>
<dependency>
<groupId>org.elasticsearch</groupId>
<artifactId>elasticsearch</artifactId>
<version>7.2.0</version>
</dependency>
索引信息：
- 索引分片：2
- 索引副本：1
- 索引总字段数：10000
- kibana 的索引大小：总计-
27.2 MB & Primaries: 12.2MB
- 索引结构：
{
"dev-index": {
"mappings": {
"properties": {
"dataObj": {
"type": "object",
"enabled": false
},
"generatedID": {
"type": "keyword"
},
"transNames": { //it's array of string
"type": "keyword"
}
}
}
}
}
- 动态映射已禁用。
以下是我的 elastic Config 文件。这里我有两个连接 bean，一个用于读取，另一个用于写入 elastic。
ElasticConfig.java:
@Configuration
public class ElasticConfig {
@Value("${elastic.host}")
private String elasticHost;
@Value("${elastic.port}")
private int elasticPort;
@Value("${elastic.user}")
private String elasticUser;
@Value("${elastic.pass}")
private String elasticPass;
@Value("${elastic-timeout:20}")
private int timeout;
@Bean(destroyMethod = "close")
@Qualifier("readClient")
public RestHighLevelClient readClient(){
final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(elasticUser, elasticPass));
RestClientBuilder builder = RestClient
.builder(new HttpHost(elasticHost, elasticPort))
.setHttpClientConfigCallback(httpClientBuilder ->
httpClientBuilder
.setDefaultCredentialsProvider(credentialsProvider)
.setDefaultIOReactorConfig(IOReactorConfig.custom().setIoThreadCount(5).build())
);
builder.setRequestConfigCallback(requestConfigBuilder ->
requestConfigBuilder
.setConnectTimeout(10000)
.setSocketTimeout(60000)
.setConnectionRequestTimeout(0)
);
RestHighLevelClient restClient = new RestHighLevelClient(builder);
return restClient;
}
@Bean(destroyMethod = "close")
@Qualifier("writeClient")
public RestHighLevelClient writeClient(){
final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(elasticUser, elasticPass));
RestClientBuilder builder = RestClient
.builder(new HttpHost(elasticHost, elasticPort))
.setHttpClientConfigCallback(httpClientBuilder ->
httpClientBuilder
.setDefaultCredentialsProvider(credentialsProvider)
.setDefaultIOReactorConfig(IOReactorConfig.custom().setIoThreadCount(5).build())
);
builder.setRequestConfigCallback(requestConfigBuilder ->
requestConfigBuilder
.setConnectTimeout(10000)
.setSocketTimeout(60000)
.setConnectionRequestTimeout(0)
);
RestHighLevelClient restClient = new RestHighLevelClient(builder);
return restClient;
}
}
这是调用 elastic 的函数，如果数据在 elastic 中可用，它将获取它，否则它将生成数据并放入 elastic。
public Object getData(Request request) {
DataObj elasticResult = elasticService.getData(request);
if(elasticResult!=null){
return elasticResult;
}
else{
//code to generate data
DataObj generatedData = getData();//some function which will generated data
//put above data into elastic by Async call.
elasticAsync.putData(generatedData);
return generatedData;
}
}
ElasticService.java 获取数据函数：
@Service
public class ElasticService {
@Value("${elastic.index}")
private String elasticIndex;
@Autowired
@Qualifier("readClient")
private RestHighLevelClient readClient;
public DataObj getData(Request request){
String generatedId = request.getGeneratedID();
GetRequest getRequest = new GetRequest()
.index(elasticIndex) //elastic index name
.id(generatedId); //retrieving by index id from elastic _id field (as key-value)
DataObj result = null;
try {
GetResponse response = readClient.get(getRequest, RequestOptions.DEFAULT);
if(response.isExists()) {
ObjectMapper objectMapper = new ObjectMapper();
result = objectMapper.readValue(response.getSourceAsString(), DataObj.class);
}
} catch (Exception e) {
LOGGER.error("Exception occurred during fetch from elastic !!!! " + ,e);
}
return result;
}
}
ElasticAsync.java 异步放置数据函数：
@Service
public class ElasticAsync {
private static final Logger LOGGER = Logger.getLogger(ElasticAsync.class.getName());
@Value("${elastic.index}")
private String elasticIndex;
@Autowired
@Qualifier("writeClient")
private RestHighLevelClient writeClient;
@Async
public void putData(DataObj generatedData){
ElasticVO updatedRequest = toElasticVO(generatedData);//ElasticVO matches to the structure of index given above.
try {
ObjectMapper objectMapper = new ObjectMapper();
String jsonString = objectMapper.writeValueAsString(updatedRequest);
IndexRequest request = new IndexRequest(elasticIndex);
request.id(generatedData.getGeneratedID());
request.source(jsonString, XContentType.JSON);
request.setRefreshPolicy(WriteRequest.RefreshPolicy.NONE);
request.timeout(TimeValue.timeValueSeconds(5));
IndexResponse indexResponse = writeClient.index(request, RequestOptions.DEFAULT);
LOGGER.info("response id: " + indexResponse.getId());
}
} catch (Exception e) {
LOGGER.error("Exception occurred during saving into elastic !!!!",e);
}
}
}
这是在将数据保存到 elastic 中时发生异常时堆栈跟踪的某些部分：
2019-07-19 07:32:19.997 ERROR [data-retrieval,341e6ecc5b10f3be,1eeb0722983062b2,true] 1 --- [askExecutor-894] a.c.s.a.service.impl.ElasticAsync : Exception occurred during saving into elastic !!!!
java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-34 [ACTIVE]
at org.elasticsearch.client.RestClient.extractAndWrapCause(RestClient.java:789) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:225) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:212) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1448) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1418) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1388) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.index(RestHighLevelClient.java:836) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
Caused by: java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-34 [ACTIVE]
at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.timeout(HttpAsyncRequestExecutor.java:387) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:92) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:39) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.reactor.AbstractIODispatch.timeout(AbstractIODispatch.java:175) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.sessionTimedOut(BaseIOReactor.java:263) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.timeoutCheck(AbstractIOReactor.java:492) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.validate(BaseIOReactor.java:213) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:280) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:591) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
... 1 common frames omitted
这是在将数据检索到 elastic 中时发生异常时堆栈跟踪的某些部分：
2019-07-19 07:22:37.844 ERROR [data-retrieval,104cf6b2ab5b3349,b302d3d3cd7ebc84,true] 1 --- [o-8080-exec-346] a.c.s.a.service.impl.ElasticService : Exception occurred during fetch from elastic !!!!
java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-30 [ACTIVE]
at org.elasticsearch.client.RestClient.extractAndWrapCause(RestClient.java:789) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:225) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:212) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1433) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1403) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1373) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.get(RestHighLevelClient.java:699) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
Caused by: java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-30 [ACTIVE]
at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.timeout(HttpAsyncRequestExecutor.java:387) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:92) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:39) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.reactor.AbstractIODispatch.timeout(AbstractIODispatch.java:175) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.sessionTimedOut(BaseIOReactor.java:263) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.timeoutCheck(AbstractIOReactor.java:492) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.validate(BaseIOReactor.java:213) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:280) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:591) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
... 1 common frames omitted
我浏览了几个 Whosebug 和 elastic 相关的博客，他们提到这个问题可能是由于弹性的 RAM 和 cluster 配置造成的。然后我将分片从 5 个更改为 2 个，因为只有两个数据节点。还将数据节点的 ram 从 4GB 增加到 8GB，因为我知道弹性将仅使用总数 RAM 的 50%。异常的发生次数减少了，但问题仍然存在。
有什么可能的方法可以解决这个问题？从经常抛出这种 SocketTimeoutException 的 java/elastic 配置角度来看，我缺少什么？如果您需要有关配置的更多详细信息，请告诉我。
我们遇到了同样的问题，经过相当多的挖掘后，我找到了根本原因：客户端与弹性服务器内核配置之间的防火墙配置不匹配，以保持 tcp 保持活动状态。
防火墙在 3600 秒后丢弃空闲连接。问题是 tcp keep alive 的内核参数设置为 7200 秒（RedHat 6 中的默认值。x/7.x）：
sysctl -n net.ipv4.tcp_keepalive_time
7200
因此，在发送保持活动探测之前，连接已断开。弹性http客户端中的asyncHttpClient似乎不能很好地处理掉线，它只是等到套接字超时。
因此请检查您的客户端和服务器之间是否有任何网络设备（负载均衡器、防火墙、代理等）出现会话超时或类似情况，并增加该超时或降低 tcp_keep_alive 内核参数。
我面对 SocketTimeoutException 而 retrieving/inserting 数据 from/to 弹性。当大约 10-30 request/second 时就会发生这种情况。这些请求是 get/put.
这是我的弹性配置：
3 master nodes每个4GB RAM2 data nodes每个8GM RAM- 连接到上述数据节点的 Azure 负载均衡器（似乎只打开了 9200 端口）。 java 客户端连接到此负载均衡器，因为它只公开。
- 弹性版本：7.2.0
其余高级客户：
<dependency> <groupId>org.elasticsearch.client</groupId> <artifactId>elasticsearch-rest-high-level-client</artifactId> <version>7.2.0</version> </dependency> <dependency> <groupId>org.elasticsearch</groupId> <artifactId>elasticsearch</artifactId> <version>7.2.0</version> </dependency>
索引信息：
- 索引分片：2
- 索引副本：1
- 索引总字段数：10000
- kibana 的索引大小：总计-
27.2 MB&Primaries: 12.2MB - 索引结构：
{ "dev-index": { "mappings": { "properties": { "dataObj": { "type": "object", "enabled": false }, "generatedID": { "type": "keyword" }, "transNames": { //it's array of string "type": "keyword" } } } } } - 动态映射已禁用。
以下是我的 elastic Config 文件。这里我有两个连接 bean，一个用于读取，另一个用于写入 elastic。
ElasticConfig.java:
@Configuration
public class ElasticConfig {
@Value("${elastic.host}")
private String elasticHost;
@Value("${elastic.port}")
private int elasticPort;
@Value("${elastic.user}")
private String elasticUser;
@Value("${elastic.pass}")
private String elasticPass;
@Value("${elastic-timeout:20}")
private int timeout;
@Bean(destroyMethod = "close")
@Qualifier("readClient")
public RestHighLevelClient readClient(){
final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(elasticUser, elasticPass));
RestClientBuilder builder = RestClient
.builder(new HttpHost(elasticHost, elasticPort))
.setHttpClientConfigCallback(httpClientBuilder ->
httpClientBuilder
.setDefaultCredentialsProvider(credentialsProvider)
.setDefaultIOReactorConfig(IOReactorConfig.custom().setIoThreadCount(5).build())
);
builder.setRequestConfigCallback(requestConfigBuilder ->
requestConfigBuilder
.setConnectTimeout(10000)
.setSocketTimeout(60000)
.setConnectionRequestTimeout(0)
);
RestHighLevelClient restClient = new RestHighLevelClient(builder);
return restClient;
}
@Bean(destroyMethod = "close")
@Qualifier("writeClient")
public RestHighLevelClient writeClient(){
final CredentialsProvider credentialsProvider = new BasicCredentialsProvider();
credentialsProvider.setCredentials(AuthScope.ANY, new UsernamePasswordCredentials(elasticUser, elasticPass));
RestClientBuilder builder = RestClient
.builder(new HttpHost(elasticHost, elasticPort))
.setHttpClientConfigCallback(httpClientBuilder ->
httpClientBuilder
.setDefaultCredentialsProvider(credentialsProvider)
.setDefaultIOReactorConfig(IOReactorConfig.custom().setIoThreadCount(5).build())
);
builder.setRequestConfigCallback(requestConfigBuilder ->
requestConfigBuilder
.setConnectTimeout(10000)
.setSocketTimeout(60000)
.setConnectionRequestTimeout(0)
);
RestHighLevelClient restClient = new RestHighLevelClient(builder);
return restClient;
}
}
这是调用 elastic 的函数，如果数据在 elastic 中可用，它将获取它，否则它将生成数据并放入 elastic。
public Object getData(Request request) {
DataObj elasticResult = elasticService.getData(request);
if(elasticResult!=null){
return elasticResult;
}
else{
//code to generate data
DataObj generatedData = getData();//some function which will generated data
//put above data into elastic by Async call.
elasticAsync.putData(generatedData);
return generatedData;
}
}
ElasticService.java 获取数据函数：
@Service
public class ElasticService {
@Value("${elastic.index}")
private String elasticIndex;
@Autowired
@Qualifier("readClient")
private RestHighLevelClient readClient;
public DataObj getData(Request request){
String generatedId = request.getGeneratedID();
GetRequest getRequest = new GetRequest()
.index(elasticIndex) //elastic index name
.id(generatedId); //retrieving by index id from elastic _id field (as key-value)
DataObj result = null;
try {
GetResponse response = readClient.get(getRequest, RequestOptions.DEFAULT);
if(response.isExists()) {
ObjectMapper objectMapper = new ObjectMapper();
result = objectMapper.readValue(response.getSourceAsString(), DataObj.class);
}
} catch (Exception e) {
LOGGER.error("Exception occurred during fetch from elastic !!!! " + ,e);
}
return result;
}
}
ElasticAsync.java 异步放置数据函数：
@Service
public class ElasticAsync {
private static final Logger LOGGER = Logger.getLogger(ElasticAsync.class.getName());
@Value("${elastic.index}")
private String elasticIndex;
@Autowired
@Qualifier("writeClient")
private RestHighLevelClient writeClient;
@Async
public void putData(DataObj generatedData){
ElasticVO updatedRequest = toElasticVO(generatedData);//ElasticVO matches to the structure of index given above.
try {
ObjectMapper objectMapper = new ObjectMapper();
String jsonString = objectMapper.writeValueAsString(updatedRequest);
IndexRequest request = new IndexRequest(elasticIndex);
request.id(generatedData.getGeneratedID());
request.source(jsonString, XContentType.JSON);
request.setRefreshPolicy(WriteRequest.RefreshPolicy.NONE);
request.timeout(TimeValue.timeValueSeconds(5));
IndexResponse indexResponse = writeClient.index(request, RequestOptions.DEFAULT);
LOGGER.info("response id: " + indexResponse.getId());
}
} catch (Exception e) {
LOGGER.error("Exception occurred during saving into elastic !!!!",e);
}
}
}
这是在将数据保存到 elastic 中时发生异常时堆栈跟踪的某些部分：
2019-07-19 07:32:19.997 ERROR [data-retrieval,341e6ecc5b10f3be,1eeb0722983062b2,true] 1 --- [askExecutor-894] a.c.s.a.service.impl.ElasticAsync : Exception occurred during saving into elastic !!!!
java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-34 [ACTIVE]
at org.elasticsearch.client.RestClient.extractAndWrapCause(RestClient.java:789) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:225) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:212) ~[elasticsearch-rest-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1448) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1418) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1388) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
at org.elasticsearch.client.RestHighLevelClient.index(RestHighLevelClient.java:836) ~[elasticsearch-rest-high-level-client-7.2.0.jar!/:7.2.0]
Caused by: java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-34 [ACTIVE]
at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.timeout(HttpAsyncRequestExecutor.java:387) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:92) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:39) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.reactor.AbstractIODispatch.timeout(AbstractIODispatch.java:175) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.sessionTimedOut(BaseIOReactor.java:263) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.timeoutCheck(AbstractIOReactor.java:492) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.validate(BaseIOReactor.java:213) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:280) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:591) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
... 1 common frames omitted
这是在将数据检索到 elastic 中时发生异常时堆栈跟踪的某些部分：
2019-07-19 07:22:37.844 ERROR [data-retrieval,104cf6b2ab5b3349,b302d3d3cd7ebc84,true] 1 --- [o-8080-exec-346] a.c.s.a.service.impl.ElasticService : Exception occurred during fetch from elastic !!!!
java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-30 [ACTIVE]
at org.elasticsearch.client.RestClient.extractAndWrapCause(RestClient.java:789) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:225) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestClient.performRequest(RestClient.java:212) ~[elasticsearch-rest-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.internalPerformRequest(RestHighLevelClient.java:1433) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.performRequest(RestHighLevelClient.java:1403) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.performRequestAndParseEntity(RestHighLevelClient.java:1373) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
at org.elasticsearch.client.RestHighLevelClient.get(RestHighLevelClient.java:699) ~[elasticsearch-rest-high-level-client-7.1.1.jar!/:7.1.1]
Caused by: java.net.SocketTimeoutException: 60,000 milliseconds timeout on connection http-outgoing-30 [ACTIVE]
at org.apache.http.nio.protocol.HttpAsyncRequestExecutor.timeout(HttpAsyncRequestExecutor.java:387) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:92) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.client.InternalIODispatch.onTimeout(InternalIODispatch.java:39) ~[httpasyncclient-4.1.3.jar!/:4.1.3]
at org.apache.http.impl.nio.reactor.AbstractIODispatch.timeout(AbstractIODispatch.java:175) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.sessionTimedOut(BaseIOReactor.java:263) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.timeoutCheck(AbstractIOReactor.java:492) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.validate(BaseIOReactor.java:213) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractIOReactor.execute(AbstractIOReactor.java:280) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.BaseIOReactor.execute(BaseIOReactor.java:104) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
at org.apache.http.impl.nio.reactor.AbstractMultiworkerIOReactor$Worker.run(AbstractMultiworkerIOReactor.java:591) ~[httpcore-nio-4.4.11.jar!/:4.4.11]
... 1 common frames omitted
我浏览了几个 Whosebug 和 elastic 相关的博客，他们提到这个问题可能是由于弹性的 RAM 和 cluster 配置造成的。然后我将分片从 5 个更改为 2 个，因为只有两个数据节点。还将数据节点的 ram 从 4GB 增加到 8GB，因为我知道弹性将仅使用总数 RAM 的 50%。异常的发生次数减少了，但问题仍然存在。
有什么可能的方法可以解决这个问题？从经常抛出这种 SocketTimeoutException 的 java/elastic 配置角度来看，我缺少什么？如果您需要有关配置的更多详细信息，请告诉我。
我们遇到了同样的问题，经过相当多的挖掘后，我找到了根本原因：客户端与弹性服务器内核配置之间的防火墙配置不匹配，以保持 tcp 保持活动状态。
防火墙在 3600 秒后丢弃空闲连接。问题是 tcp keep alive 的内核参数设置为 7200 秒（RedHat 6 中的默认值。x/7.x）：
sysctl -n net.ipv4.tcp_keepalive_time
7200
因此，在发送保持活动探测之前，连接已断开。弹性http客户端中的asyncHttpClient似乎不能很好地处理掉线，它只是等到套接字超时。
因此请检查您的客户端和服务器之间是否有任何网络设备（负载均衡器、防火墙、代理等）出现会话超时或类似情况，并增加该超时或降低 tcp_keep_alive 内核参数。