我已经使用以下网站的manul安装和配置hadoop作为单个节点。
我编译了wordcount示例并运行它，但需要很长时间并生成Shuffle Error: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.
hduser@aptunix0043:/usr/local/hadoop/src$ hadoop jar WordCount.jar org/apache/hadoop/examples/WordCount input ot
****hdfs://localhost:54310/user/hduser/input
12/07/03 02:52:35 INFO input.FileInputFormat: Total input paths to process : 1
12/07/03 02:52:36 INFO mapred.JobClient: Running job: job_201207030248_0002
12/07/03 02:52:37 INFO mapred.JobClient: map 0% reduce 0%
12/07/03 02:52:52 INFO mapred.JobClient: map 100% reduce 0%
12/07/03 03:21:26 INFO mapred.JobClient: Task Id :attempt_201207030248_0002_r_000000_0, Status : FAILED
Shuffle Error: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.
12/07/03 03:21:47 WARN mapred.JobClient: Error reading task outputConnection timed out
12/07/03 03:22:08 WARN mapred.JobClient: Error reading task outputConnection timed out
/user/hduser/input/*12/07/03 03:50:01 INFO mapred.JobClient: Task Id : attempt_201207030248_0002_r_000000_1, Status : FAILED
Shuffle Error: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.
12/07/03 03:50:22 WARN mapred.JobClient: Error reading task outputConnection timed out
12/07/03 03:50:43 WARN mapred.JobClient: Error reading task outputConnection timed out
12/07/03 04:18:35 INFO mapred.JobClient: Task Id : attempt_201207030248_0002_r_000000_2, Status : FAILED
Shuffle Error: Exceeded MAX_FAILED_UNIQUE_FETCHES; bailing-out.
12/07/03 04:18:56 WARN mapred.JobClient: Error reading task outputConnection timed out
12/07/03 04:19:17 WARN mapred.JobClient: Error reading task outputConnection timed out
12/07/03 04:47:15 INFO mapred.JobClient: Job complete: job_201207030248_0002
12/07/03 04:47:15 INFO mapred.JobClient: Counters: 23
12/07/03 04:47:15 INFO mapred.JobClient: Job Counters
12/07/03 04:47:15 INFO mapred.JobClient: Launched reduce tasks=4
12/07/03 04:47:15 INFO mapred.JobClient: SLOTS_MILLIS_MAPS=12948
12/07/03 04:47:15 INFO mapred.JobClient: Total time spent by all reduces waiting after reserving slots (ms)=0
12/07/03 04:47:15 INFO mapred.JobClient: Total time spent by all maps waiting after reserving slots (ms)=0
12/07/03 04:47:15 INFO mapred.JobClient: Launched map tasks=1
12/07/03 04:47:15 INFO mapred.JobClient: Data-local map tasks=1
12/07/03 04:47:15 INFO mapred.JobClient: Failed reduce tasks=1
12/07/03 04:47:15 INFO mapred.JobClient: SLOTS_MILLIS_REDUCES=16469
12/07/03 04:47:15 INFO mapred.JobClient: FileSystemCounters
12/07/03 04:47:15 INFO mapred.JobClient: HDFS_BYTES_READ=661744
12/07/03 04:47:15 INFO mapred.JobClient: FILE_BYTES_WRITTEN=288616
12/07/03 04:47:15 INFO mapred.JobClient: File Input Format Counters
12/07/03 04:47:15 INFO mapred.JobClient: Bytes Read=661630
12/07/03 04:47:15 INFO mapred.JobClient: Map-Reduce Framework
12/07/03 04:47:15 INFO mapred.JobClient: Map output materialized bytes=267085
12/07/03 04:47:15 INFO mapred.JobClient: Combine output records=18040
12/07/03 04:47:15 INFO mapred.JobClient: Map input records=12761
12/07/03 04:47:15 INFO mapred.JobClient: Physical memory (bytes) snapshot=183209984
12/07/03 04:47:15 INFO mapred.JobClient: Spilled Records=18040
12/07/03 04:47:15 INFO mapred.JobClient: Map output bytes=1086716
12/07/03 04:47:15 INFO mapred.JobClient: CPU time spent (ms)=1940
12/07/03 04:47:15 INFO mapred.JobClient: Total committed heap usage (bytes)=162856960
12/07/03 04:47:15 INFO mapred.JobClient: Virtual memory (bytes) snapshot=393482240
12/07/03 04:47:15 INFO mapred.JobClient: Combine input records=109844
12/07/03 04:47:15 INFO mapred.JobClient: Map output records=109844
12/07/03 04:47:15 INFO mapred.JobClient: SPLIT_RAW_BYTES=114
任何线索？
答案 0 :(得分：1)
为了帮助那些在互联网上搜索并像我这样访问此页面的人，您可能会遇到2个问题
DNS解析 - 确保在安装hadoop时为每台主机使用完全限定的域名
防火墙 - 防火墙可能会阻止端口50060,50030以及基于您的hadoop分发的更多端口（cloudera为7182,7180）
答案 1 :(得分：0)
之前我遇到此错误，它是由DNS问题引起的。你在基于Linux的发行版中运行吗？如果是这样，请确保所有/ etc / hosts都是同步的，在我的情况下，我使用了每个节点“slave1 192.168.1.23”等的别名......但是这与盒子名称不匹配所以我不得不改变它，或者你可以改变你的盒子名称，以匹配hadoop conf中“奴隶”对应的那个。