我正在尝试使用单节点集群（psuedo分布式）来设置hadoop，并使用apache指南来实现这一点。现在我正在尝试运行mapreduce作业，并使用它提供的示例 bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.0.0-alpha3.jar grep input output 'dfs[a-z]+' ```
hadoop@hadoop:/usr/local/hadoop$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-3.0.0-alpha3.jar grep input output 'dfs[a-z]+'
xxxx-xx-xx xx:xx:xx,xxx INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
xxxx-xx-xx xx:xx:xx,xxx INFO ipc.Client: Retrying connect to server: 0.0.0.0/0.0.0.0:8032. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1000 MILLISECONDS)
xxxx-xx-xx xx:xx:xx,xxx INFO ipc.Client: Retrying connect to server: 0.0.0.0/0.0.0.0:8032. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1000 MILLISECONDS)
...
xxxx-xx-xx xx:xx:xx,xxx INFO ipc.Client: Retrying connect to server: 0.0.0.0/0.0.0.0:8032. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1000 MILLISECONDS)
xxxx-xx-xx xx:xx:xx,xxx WARN ipc.Client: Failed to connect to server: 0.0.0.0/0.0.0.0:8032: retries get failed due to exceeded maximum allowed retries number: 10
java.net.ConnectException: Connection refused
at java.base/sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at java.base/sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)
at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)

在网上查找此问题时，其他有此问题的人似乎都与yarn有关，而不是mapreduce。我的hdfs-site.xml与指南中提到的相同：