Accessing HDFS file systems

Read(149) Label: hdfsfilecli,

1. Find the following jars in Hadoop installation directory and put them in esProc external library folder. Get the appropriate jars according to the Hadoop version you are using. The directory containing files of this external library is: installation directory\esProc\extlib\HdfsFileCli. The Raqsoft core jar for this external library is HdfsFileCli.jar.

commons-cli-1.2.jar

commons-collections-3.2.2.jar

commons-configuration-1.6.jar

commons-lang-2.6.jar

guava-11.0.2.jar

hadoop-auth-2.6.5.jar

hadoop-common-2.6.5.jar

hadoop-hdfs-2.6.5.jar

hadoop-mapreduce-client-core-2.6.5.jar

hadoop-mapreduce-client-jobclient-2.6.5.jar

htrace-core-3.0.4.jar

log4j-1.2.17.jar

protobuf-java-2.5.0.jar

slf4j-api-1.7.5.jar

slf4j-log4j12-1.7.5.jar

Note: The third-party jars are provided within the package and users can choose appropriate ones for specific scenarios..

·The following two jars are also needed for Hadoop2.8.3 version:

hadoop-hdfs-client-2.8.3.jar

htrace-core4-4.0.1-incubating.jar

·The following 5 jars are also needed for Hadoop 3.0.0 version:

hadoop-client-runtime-3.0.0

hadoop-hdfs-client-3.0.0.jar

htrace-core4-4.1.0-incubating.jar

stax2-api-3.1.4.jar

woodstox-core-5.0.3.jar

Besides, use commons-configuration2-2.1.1.jar to replace commons-configuration-1.6.jar in a lower version.

 

2. Download the following four files from the web and place them in installation directory\bin:

hadoop.dll

hadoop.lib

libwinutils.lib

winutils.exe

Note: The above files are required under Windows environment, but not under Linux. There are x86 winutils.exe and x64 winutils.exe depending on different OS versions.

 

3. A JRE version 1.7 or above is required. The embedded JRE version in esProc is JRE1.6. Users need to install a higher version and configure java_home in the config.txt under installation directory\esProc\bin. If a JDK version 1.7 or above has been chosen when installing esProc, just ignore this step.

 

4. Users can manually change the size of memory if the default size isn’t large enough for needs. Two ways to manage memory under Windows are available: Change the memory settings in config.txt when starting esProc through the executable file; and in the .bat file when starting the application through the batch file. Under Linux, change the memory size in the .sh file.

Below is the method of changing memory settings in config.txt under Windows:

java_home=C:\ProgramFiles\Java\JDK1.7.0_11;esproc_port=48773;jvm_args=-Xms256m -XX:PermSize=256M -XX:MaxPermSize=512M -Xmx9783m -Duser.language=zh

 

5. On the machine where esProc is installed, find the hosts file to add the IP address and hostname of the machine holding the HDFS file system. For example, if the IP address and hostname are 192.168.0.8 and masters respectively, here are the settings:

 

6. esProc provides a number of external library functions, including hdfsfile(), hdfs_client(), hdfs_close(), hdfs_file(), hdfs_dir() and so on, to access the HDFS file system. Look up them inHelp-Function referenceto find the uses.