【发布时间】：2013-08-06 00:05:46
【问题描述】：
我已经安装了 Cloudera Hadoop-LZO 包并将以下设置添加到我的客户端环境安全阀中：
HADOOP_CLASSPATH=$HADOOP_CLASSPATH:/opt/cloudera/parcels/HADOOP_LZO/lib/hadoop/lib/*
JAVA_LIBRARY_PATH=$JAVA_LIBRARY_PATH:/opt/cloudera/parcels/HADOOP_LZO/lib/hadoop/lib/native
但是，我得到了最奇怪的 native-lzo library not available 错误：
13/08/05 23:59:06 INFO lzo.GPLNativeCodeLoader: Loaded native gpl library
13/08/05 23:59:06 INFO lzo.LzoCodec: Successfully loaded & initialized native-lzo library [hadoop-lzo rev 6298911ef75545c61859c08add6a74a83e0183ad]
13/08/05 23:59:07 INFO mapred.JobClient: Running job: job_201308052350_0003
13/08/05 23:59:08 INFO mapred.JobClient: map 0% reduce 0%
13/08/05 23:59:18 INFO mapred.JobClient: Task Id : attempt_201308052350_0003_m_000000_0, Status : FAILED
java.lang.RuntimeException: native-lzo library not available
at com.hadoop.compression.lzo.LzopCodec.getDecompressorType(LzopCodec.java:96)
at org.apache.hadoop.io.compress.CodecPool.getDecompressor(CodecPool.java:131)
at org.apache.hadoop.mapreduce.lib.input.LineRecordReader.initialize(LineRecordReader.java:86)
at org.apache.hadoop.mapred.MapTask$NewTrackingRecordReader.initialize(MapTask.java:478)
at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:671)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:330)
at org.apache.hadoop.mapred.Child$4.run(Child.java:268)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:396)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1408)
at org.apache.hadoop.mapred.Child.main(Child.java:262)
为什么会说native-lzo库加载成功，然后又抱怨native-lzo库不可用？这些异常是否来自 DataNode？p>
【问题讨论】：
-
加载的日志意味着native-lzo已经加载到JobClient中。但投诉来自映射器。这意味着 TaskTracker 找不到 native-lzo。