Spark问题解决 - 运行bin/run-example SparkPi 4 4出错

之前Spark用的是集群模式，今天试试本地模式，运行样例报错。

错误如下：

[root@s210 spark-2.2.0]# bin/run-example SparkPi 4 4
Using Spark's default log4j profile: org/apache/spark/log4j-defaults.properties
18/08/13 17:09:42 INFO SparkContext: Running Spark version 2.2.0
18/08/13 17:09:42 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Exception in thread "main" java.lang.ExceptionInInitializerError
        at org.apache.spark.SparkConf.validateSettings(SparkConf.scala:546)
        at org.apache.spark.SparkContext.(SparkContext.scala:373)
        at org.apache.spark.SparkContext$.getOrCreate(SparkContext.scala:2509)
        at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:909)
        at org.apache.spark.sql.SparkSession$Builder$$anonfun$6.apply(SparkSession.scala:901)
        at scala.Option.getOrElse(Option.scala:121)
        at org.apache.spark.sql.SparkSession$Builder.getOrCreate(SparkSession.scala:901)
        at org.apache.spark.examples.SparkPi$.main(SparkPi.scala:31)
        at org.apache.spark.examples.SparkPi.main(SparkPi.scala)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:497)
        at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:755)
        at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:180)
        at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:205)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:119)
▽       at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Caused by: java.net.UnknownHostException: s210: s210: unknown error
        at java.net.InetAddress.getLocalHost(InetAddress.java:1505)
        at org.apache.spark.util.Utils$.findLocalInetAddress(Utils.scala:891)
        at org.apache.spark.util.Utils$.org$apache$spark$util$Utils$$localIpAddress$lzycompute(Utils.scala:884)
        at org.apache.spark.util.Utils$.org$apache$spark$util$Utils$$localIpAddress(Utils.scala:884)
        at org.apache.spark.util.Utils$$anonfun$localHostName$1.apply(Utils.scala:941)
        at org.apache.spark.util.Utils$$anonfun$localHostName$1.apply(Utils.scala:941)
        at scala.Option.getOrElse(Option.scala:121)
        at org.apache.spark.util.Utils$.localHostName(Utils.scala:941)
        at org.apache.spark.internal.config.package$.(package.scala:204)
        at org.apache.spark.internal.config.package$.(package.scala)
        ... 18 more
Caused by: java.net.UnknownHostException: s210: unknown error
        at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
        at java.net.InetAddress$2.lookupAllHostAddr(InetAddress.java:928)
        at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1323)
        at java.net.InetAddress.getLocalHost(InetAddress.java:1500)
        ... 27 more

解决：

这是由于/etc/hosts文件没有配置

源文件：

添加为：

再次运行即可解决。