hadoop hdfs tutorial

3rd Chapter HDFS: Distributed File System 3.5 HDFs Basic Command HDFs Order Official documents:http://hadoop.apache.org/docs/r2.7.3/hadoop-project-dist/hadoop-hdfs/HDFSCommands.html 3.5.1 Usage [Root@node1 ~]#

-02-06 17:41/user/test_hiveCan see the creation of a folder belonging to HTTPFS. ABC Open File upload a text file from the background test.txt to the/USER/ABC directory, the content isHello world!Access with HTTPFS[[email protected] hadoop-httpfs]# curl-i-x GET "http://xmseapp03:14000/webhdfs/v1/user/abc/test.txt?op=open User.name=httpfs "http/1.1 okserver:apache-coyote/1.1set-cookie:hadoop.auth=" u=httpfsp=httpfst= Simplee=1423574166943s=jtxqijusblvb

Install times wrong: Failed to execute goal org.apache.maven.plugins:maven-antrun-plugin:1.7:run (site) on project Hadoop-hdfs:an Ant B Uildexception has occured:input file/usr/local/hadoop-2.6.0-stable/hadoop-2.6.0-src/hadoop-hdfs-project/

HDFs Add Delete nodes and perform HDFs balance Mode 1: Static add Datanode, stop Namenode mode 1. Stop Namenode 2. Modify the slaves file and update to each node 3. Start Namenode 4. Execute the Hadoop balance command. (This is used for the balance cluster and is not required if you are just adding a node) ----------------------------------------- Mode 2:

4th Chapter HDFs java API 4.5 Java API Introduction In section 4.4 We already know the HDFs Java API configuration, filesystem, path, and other classes, this section will detail the HDFs Java API, a section to demonstrate more applications. 4.5.1 Java API website Hadoop 2.7.3 Java API official addressHttp://hadoop.ap

"), also add our standard Spark classpath, built using compute-classpath.sh. Classpath= ' $FWDIR/bin/compute-classpath.sh ' Classdata-path= "$SPARK _qiutest_jar: $CLASSPATH" # find Java Binary If [-N "${java_home}"]; Then Runner= "${java_home}/bin/java" Else If [' command-v Java ']; Then Runner= "Java" Else echo "Java_home is not set" >2 Exit 1 Fi Fi If ["$SPARK _print_launch_command" = = "1"]; Then Echo-n "Spark Command:" echo "$RUNNER"-CP "$CLASSPATH" "$@" echo "=============================

Under the Cd/home/hadoop/hadoop-2.5.2/binPerformed by the./hdfs Namenode-formatError[Email protected] bin]$/hdfs Namenode–format16/07/11 09:21:21 INFO Namenode. Namenode:startup_msg:/************************************************************Startup_msg:starting NameNodeStartup_msg:host = node1/192.168.8.11Startup_msg

now let's take a closer look at the FileSystem class for Hadoop. This class is used to interact with Hadoop's file system. While we are mainly targeting HDFS here, we should let our code use only abstract class filesystem so that our code can interact with any Hadoop file system. When we write the test code, we can test it with the local file system, use

Chapter 2 mapreduce IntroductionAn ideal part size is usually the size of an HDFS block. The execution node of the map task and the storage node of the input data are the same node, and the hadoop performance is optimal (Data Locality optimization, avoid data transmission over the network ). Mapreduce Process summary: reads a row of data from a file, map function processing, Return key-value pairs; the sys

Multiple interfaces are available to access HDFS. The command line interface is the simplest and the most familiar method for programmers. In this example, HDFS in pseudo sodistributed mode is used to simulate a distributed file system. For more information about how to configure the pseudo-distributed mode, see configure: This means that the default file system of hado