hadoop connection refused
在执行 hadoop jar $HADOOP_HOME/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.4.1.jar grep /user/hadoop/input / output 时,会报如下错误:
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Application application_1422517158532_0004 failed 2 times due to Error launching appattempt_1422517158532_0004_000002. Got exception: java.net.ConnectException: Call From master/192.168.12.250 to master:53450 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused
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备注:防火墙已经全部关闭。
请问,这个问题应该如何解?