rhdfs没有建立连接

Question

I have set the HADOOP_CMD (hadoop path) variable but it is not taking the path,saying as not found

library("rhdfs")
hdfs.init()
Sys.setenv(HADOOP_CMD="C:/cygwin64/usr/local/hadoop/bin/hadoop") 
Error in system(command, intern = TRUE) : 
'C:/cygwin64/usr/local/hadoop/bin/hadoop' not found

I have defind HADOOP_CMD in system env variable also as well as in cygwin by

export HADOOP_CMD="C:/cygwin64/usr/local/hadoop/bin/hadoop"

where am i wrong,any help in this direction,thanks.

Answer 1

HADOOP_HOME & HADOOP_CMD should be set in R session, before calling hdfs.init()

Also remember following checkpoint before staring RHadoop

• R-Hadoop dependencies

  • rmr2 - RCpp, RJSONIO, digest, functional, stringr, plyr
  • rhdfs - rJava

• Export env variables in R Session before running init()

  # requied
Sys.setenv(HADOOP_HOME="/home/trendwise/apache/hadoop-1.0.4"); Sys.setenv(HADOOP_CMD="/home/trendwise/apache/hadoop-1.0.4/bin/hadoop"); Sys.setenv(HADOOP_STREAMING='/home/trendwise/apache/hadoop-1.0.4/contrib/streaming/hadoop-streaming-1.0.4.jar')

  #optional
Sys.setenv(HADOOP_BIN="/home/trendwise/apache/hadoop-1.0.4/bin"); Sys.setenv(HADOOP_CONF_DIR="/home/trendwise/apache/hadoop-1.0.4/conf"); Sys.setenv(HIVE_HOME="/home/trendwise/apache/hive-0.10.0"); Sys.setenv(HBASE_HOME="/home/trendwise/apache/hbase-0.94.3");

  # Library Path Sys.setenv(LD_LIBRARY_PATH="/lib:/lib/x86_64-linux-gnu:/lib64:/usr/lib:/usr/lib64:/usr/local/lib:/usr/local/lib64:/usr/lib/jvm/jdk1.7.0_10/lib:/usr/lib/jvm/jdk1.7.0_10/jre/lib:/usr/lib/jvm/jdk1.7.0_10/jre/lib/amd64:/usr/lib/jvm/jdk1.7.0_10/jre/lib/amd64/server");

  # Loading library
library(rmr2)
library(rhdfs)

  # initializing
hdfs.init()