Hive和HBase整合,查询异常,再次执行Hive的统计命令,可能还会有异常,因为我的MapReduce前面使用过,在Hadoop中已经 加入过pro
版本说明
Hadoop 1.0.3
HBase 0.94.1
Hive 0.9.0
执行操作
hive> select count(*) from tablename;
异常提示
Exception in thread "Thread-54" java.lang.RuntimeException: Error while reading from task log url
at org.apache.hadoop.hive.ql.exec.errors.TaskLogProcessor.getStackTraces(TaskLogProcessor.java:240)
at org.apache.hadoop.hive.ql.exec.JobDebugger.showJobFailDebugInfo(JobDebugger.java:227)
at org.apache.hadoop.hive.ql.exec.JobDebugger.run(JobDebugger.java:92)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.io.IOException: Server returned HTTP response code: 400 for URL: :50060/tasklog?taskid=attempt_201212192008_0014_m_000000_3&start=-8193
at sun.net.(HttpURLConnection.java:1436)
at java.net.URL.openStream(URL.java:1010)
at org.apache.hadoop.hive.ql.exec.errors.TaskLogProcessor.getStackTraces(TaskLogProcessor.java:192)
... 3 more
解决步骤
1.异常中的路径(根据自己的异常URL地址)
:50060/tasklog?taskid=attempt_201212192008_0014_m_000000_3&start=-8193
修改为:
:50060/tasklog?attemptid=attempt_201212192008_0014_m_000000_3&start=-8193
进行访问
2.页面中有异常具体记录,我这点的异常提示是:
java.lang.NoClassDefFoundError: com/google/protobuf/Message
明显是缺少某个jar,这个jar可以在HBase的jar中找到protobuf-java-2.4.0a.jar
3.将jar放入Hive的lib目录下,修改配置文件conf/hive-site.xml
(如果前面整合过Hadoop,HBase,Hive的就知道,这里是加载Hive默认没有加载的jar)
4.再次执行Hive的统计命令,可能还会有异常,因为我的MapReduce前面使用过,,在Hadoop中已经 加入过protobuf-java-2.4.0a.jar这个jar,如果以前你没有在Hadoop的lib下加入这个jar可能也 会有异常,如果出现异常依然可以根据第一步骤的方法来查看具体的异常。
5.特别提示:如果Hadoop以前没有加入这个jar,请将集群所有的机器都加入这个jar,并重启 Hadoop或者单独重启MapReduce,重启MapReduce命令如下:
stop-mapred.sh
start-mapred.sh

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