org.apache.hadoop.hbase.client.RetriesExhaustedWithDetailsException: Failed 4 actions: UnknownHostEx

11-25 16:51:41,791:WARN hconnection-0x45c0148e-shared--pool1-t4 org.apache.hadoop.hbase.client.AsyncProcess - #1, table=global_score, attempt=11/10 failed=4ops, last exception: java.net.UnknownHostException: unknown host: uhadoop-zsmzeq-core10 on uhadoop-zsmzeq-core10,60020,1573611195929, tracking started Mon Nov 25 16:51:02 CST 2019; not retrying 4 - final failure
org.apache.hadoop.hbase.client.RetriesExhaustedWithDetailsException: Failed 4 actions: UnknownHostException: 4 times, 
        at org.apache.hadoop.hbase.client.AsyncProcess$BatchErrors.makeException(AsyncProcess.java:247)
        at org.apache.hadoop.hbase.client.AsyncProcess$BatchErrors.access$1800(AsyncProcess.java:227)
        at org.apache.hadoop.hbase.client.AsyncProcess$AsyncRequestFutureImpl.getErrors(AsyncProcess.java:1663)
        at org.apache.hadoop.hbase.client.HTable.batch(HTable.java:982)
        at org.apache.hadoop.hbase.client.HTable.batch(HTable.java:996)
        at org.apache.hadoop.hbase.client.HTable.get(HTable.java:957)
        at com.sohu.sc.service.HbaseService.findByRowKey(HbaseService.java:324)
        at com.sohu.sc.thread.TaskService.handle(TaskService.java:121)
        at com.sohu.sc.thread.TaskService.run(TaskService.java:251)
        at com.sohu.sc.thread.TaskService$$FastClassByCGLIB$$f7c83892.invoke(<generated>)
        at net.sf.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
        at org.springframework.aop.framework.Cglib2AopProxy$CglibMethodInvocation.invokeJoinpoint(Cglib2AopProxy.java:689)
        at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150)
        at org.springframework.aop.interceptor.AsyncExecutionInterceptor$1.call(AsyncExecutionInterceptor.java:83)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
        at java.lang.Thread.run(Thread.java:745)
11-25 16:51:41,793:ERROR executor-1 com.sohu.sc.thread.TaskService - run task exception msg:Failed 4 actions: UnknownHostException: 4 times, ,id:288,userId:56363,

解决：

异常信息第已经说的很清楚了，hbase连接不上。仔细看第一行有一句：unknown host: uhadoop-zsmzeq-core10 on uhadoop-zsmzeq-core10
就是说这个uhadoop-zsmzeq-core10没有找到。本地启动报错，可以在Windows hosts 文件添加uhadoop-zsmzeq-core10的配置，重启服务，hbase可以连接。

hosts文件目录：C:\Windows\System32\drivers\etc

添加配置

hosts文件：

Hosts文件主要作用是定义IP地址和主机名的映射关系，是一个映射IP地址和主机名的规定。可以用文本文件打开！当用户在浏览器中输入一个需要登录的网址时，系统会首先自动从Hosts文件中寻找对应的IP地址，一旦找到，浏览器会立即打开对应网页，如果没有找到，则浏览器会将网址提交DNS服务器进行IP地址解析。这也是提高快速打开网页的方法！

总结：

其实这个错就是hbase里面新加了一个节点，但没有在hosts里面配置，连接的时候，解析不到uhadoop-zsmzeq-core10 这个主机名