问题
RHadoop program for wordcount:
Sys.setenv(HADOOP_CMD="/usr/local/hadoop/bin/hadoop")
Sys.setenv(HADOOP_STREAMING="/usr/local/hadoop/share/hadoop/tools/lib/hadoop-streaming-2.4.1.jar")
Sys.setenv(HADOOP_HOME="/usr/local/hadoop")
library(rmr2)
## map function
map <- function(k,lines) {
words.list <- strsplit(lines, '\\s')
words <- unlist(words.list)
return( keyval(words, 1) )
}
## reduce function
reduce <- function(word, counts) {
keyval(word, sum(counts))
}
wordcount <- function (input, output=NULL) {
mapreduce(input=input, output=output, input.format="text",
map=map, reduce=reduce)
}
## Submit job
hdfs.root <- 'input'
#hdfs.data <- file.path(hdfs.root, 'data')
hdfs.out <- file.path(hdfs.root, 'out')
out <- wordcount(hdfs.root, hdfs.out)
## Fetch results from HDFS
results <- from.dfs(out)
## check top 2 frequent words
results.df <- as.data.frame(results, stringsAsFactors=F)
colnames(results.df) <- c('word', 'count')
head(results.df[order(results.df$count, decreasing=T), ], 2)
15/01/21 13:48:52 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
packageJobJar: [/usr/local/hadoop/data/hadoop-unjar5866699842450503195/] [] /tmp/streamjob7335081573862861018.jar tmpDir=null
15/01/21 13:48:53 INFO client.RMProxy: Connecting to ResourceManager at localhost/127.0.0.1:8050
15/01/21 13:48:53 INFO client.RMProxy: Connecting to ResourceManager at localhost/127.0.0.1:8050
15/01/21 13:48:53 ERROR streaming.StreamJob: Error Launching job : Permission denied: user=pgl-26, access=EXECUTE, inode="/tmp":hduser:supergroup:drwxrwx---
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkFsPermission(FSPermissionChecker.java:265)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.check(FSPermissionChecker.java:251)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkTraverse(FSPermissionChecker.java:205)
at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.checkPermission(FSPermissionChecker.java:168)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:5523)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getFileInfo(FSNamesystem.java:3521)
at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.getFileInfo(NameNodeRpcServer.java:779)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolServerSideTranslatorPB.getFileInfo(ClientNamenodeProtocolServerSideTranslatorPB.java:764)
at org.apache.hadoop.hdfs.protocol.proto.ClientNamenodeProtocolProtos$ClientNamenodeProtocol$2.callBlockingMethod(ClientNamenodeProtocolProtos.java)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Server$ProtoBufRpcInvoker.call(ProtobufRpcEngine.java:585)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:928)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2013)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:2009)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1556)
at org.apache.hadoop.ipc.Server$Handler.run(Server.java:2007)
Streaming Command Failed!
Error in mr(map = map, reduce = reduce, combine = combine, vectorized.reduce, :
hadoop streaming failed with error code 5
Please help me regarding the error. I am new to R as well as hadoop. I couldn't make sure where I have gone wrong.
回答1:
I think the issue is with permission. In the log "ERROR streaming.StreamJob: Error Launching job : Permission denied:". Please check the connectivity.
回答2:
Give permission to temp directory like hadoop fs -chown -R rhadoop /tmp
.
Where rhadoop
is username
来源:https://stackoverflow.com/questions/28063117/hadoop-streaming-failed-with-error-code-5