hadoop2

问题 I am using cloudera Hadoop 2.6, pig 0.15 versions. I am trying to extract data from xml file. Below you can see part of xml file. <product productID="MICROLITEMX1600LAMP"> <basicInfo> <category lang="NL" id="OT1006">Output Accessoires</category> </basicInfo> </product> I can dump node values but not attribute values using XPath() function. You can see the code below which is returning empty tuples instead of productID. DEFINE XPath org.apache.pig.piggybank.evaluation.xml.XPath(); allProducts

问题 I want to call hbase org.apache.hadoop.hbase.mapreduce.LoadIncrementalHFiles /user/myuser/map_data/hfiles mytable method from my Java client code. When I run the application I get the following exception: org.apache.hadoop.hbase.io.hfile.CorruptHFileException: Problem reading HFile Trailer from file webhdfs://myserver.de:50070/user/myuser/map_data/hfiles/b/b22db8e263b74a7dbd8e36f9ccf16508 at org.apache.hadoop.hbase.io.hfile.HFile.pickReaderVersion(HFile.java:477) at org.apache.hadoop.hbase.io

问题 I have taken the Hbase table backup using Hbase Export utility tool . hbase org.apache.hadoop.hbase.mapreduce.Export "FinancialLineItem" "/project/fricadev/ESGTRF/EXPORT" This has kicked in mapreduce and transferred all my table data into Output folder . As per the document the file format will of the ouotput file is sequence file . So i ran below code to extract my key and value from the file . Now i want to run mapreduce to read the key value from the output file but getting below exception

问题 Friends, I came to know that in hadoop2 when we configure high availability there is no need to configure a secondary-name-node/checkpoint-node/backup-node. With a new kind of mechanism the availability is given by edits shared among the active and standby namenodes. My question is, secondary-name-node functionality is to merge the edits file with fsimage file periodically, thus gives 2 benefits in hadoop1 world 1) limits the size of edits file and 2) reduces the time of restart by keeping

问题 I am trying to run a single node hadoop cluster on my machine with the following config: inux livingstream 3.2.0-29-generic #46-Ubuntu SMP Fri Jul 27 17:03:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux I am able to format the namenode without any problems however when I try and start the namenode using : hadoop-daemon.sh start namenode I get the following errors : ishan@livingstream:/usr/local/hadoop$ hadoop-daemon.sh start namenode Warning: $HADOOP_HOME is deprecated. mkdir: cannot create

问题 I have written mapper and reducer in python for word count program that works fine. Here is a sample: echo "hello hello world here hello here world here hello" | wordmapper.py | sort -k1,1 | wordreducer.py hello 4 here 3 world 2 Now when i try to submit a hadoop job for a large file, I get errors hadoop jar share/hadoop/tools/sources/hadoop-*streaming*.jar -file wordmapper.py -mapper wordmapper.py -file wordreducer.py -reducer wordreducer.py -input /data/1jrl.pdb -output /output/py_jrl

问题 I've installed hadoop 2.6.0 in ubuntu linux on a pseudo distributed mode. Everything is fine except this issue. When I run the start-dfs.sh script to start daemons it's asking for the linux user password. Not sure why? It's asking for the password for every daemon (namenode, datanode & sec namenode). Could you please help to address this issue? huser@ubuntu:~/hadoop$ sbin/start-dfs.sh Starting namenodes on [localhost] huser@localhost's password: Thanks in advance. 回答1: This happens if you did

问题 I am trying to copy abc.json from port/example_File/2017 to another location /port/example_File/2018 in HDFS, by below code String exampleFile= "hdfs://port/example_File/2017/abc.json" String targetFile="hdfs://port/example_File/2018" hdfs.copyFromLocalFile(new Path(exampleFile),new Path(targetFile)) I am getting below exception org.jboss.resteasy.spi.UnhandledException: java.lang.IllegalArgumentException: Wrong FS: hdfs://port/example_File/2017/abc.json, expected: file:/// How to copy file

问题 ALready Looked at Spark streaming not remembering previous state but doesn't help. Also looked at http://spark.apache.org/docs/latest/streaming-programming-guide.html#checkpointing but cant find JavaStreamingContextFactory although I am using spark streaming 2.11 v 2.0.1 My code works fine but when I restart it... it won't remember the last checkpoint... Function0<JavaStreamingContext> scFunction = new Function0<JavaStreamingContext>() { @Override public JavaStreamingContext call() throws

问题 I am implementing a left join functionality using map reduce. Left side is having around 600 million records and right side is having around 23 million records. In mapper I am making the keys using the columns used in left join condition and passing the key-value output from mapper to reducer. I am getting performance issue because of few mapper keys for which number of values in both the tables are high (eg. 456789 and 78960 respectively). Even though other reducers finish their job, these