Im trying to program with crontab a simple task, copy some files from local to HDFS. My code is this:
#!/bing/ksh
ANIO=$(date +"%Y")
MES=$(date +"%m")
DIA=$(date +"%d")
HORA=$(date +"%H")
# LOCAL AND HDFS DIRECTORIES
DIRECTORIO_LOCAL="/home/cloudera/bicing/data/$ANIO/$MES/$DIA/stations"$ANIO$MES$DIA$HORA"*"
DIRECTORIO_HDFS="/bicing/data/$ANIO/$MES/$DIA/"
# Test if the destination directory exist and create it if it's necesary
echo "hdfs dfs -test -d $DIRECTORIO_HDFS">>/home/cloudera/bicing/data/logFile
hdfs dfs -test -d $DIRECTORIO_HDFS
if [ $? != 0 ]
then
echo "hdfs dfs -mkdir -p $DIRECTORIO_HDFS">>/home/cloudera/bicing/data/logFile
hdfs dfs -mkdir -p $DIRECTORIO_HDFS
fi
# Upload the files to HDFS
echo "hdfs dfs -put $DIRECTORIO_LOCAL $DIRECTORIO_HDFS">>/home/cloudera/bicing/data/logFile
hdfs dfs -put $DIRECTORIO_LOCAL $DIRECTORIO_HDFS
As you can see is quite simple, it only define the folders variables, create the directory in HDFS (if it doesn't exists) and copies the files from local to HDFS.
The script works if I launch it directly on the Terminal but when I schedule it with Crontab it doesn't "put" the files in HDFS.
Moreover, the script creates a "logFile" with the commands that should have been executed. When I copy them to the Terminal them work perfectly.
hdfs dfs -test -d /bicing/data/2015/12/10/
hdfs dfs -mkdir -p /bicing/data/2015/12/10/
hdfs dfs -put /home/cloudera/bicing/data/2015/12/10/stations2015121022* /bicing/data/2015/12/10/
I have checked the directories and files, but I cant find the key to solve it.
Thanks in advance!!!
When you execute these commands on the console, they run fine, because "HADOOP_HOME" is set. But, when the Cron job runs, most likely, "HADOOP_HOME" environment variable is not available.
You can resolve this problem in 2 ways:
In the script, add the following statements at the beginning. This will add the paths of all the Hadoop jars to your environment.
export HADOOP_HOME={Path to your HADOOP_HOME}
export PATH=$PATH:$HADOOP_HOME\etc\hadoop\;$HADOOP_HOME\share\hadoop\common\*;$HADOOP_HOME\share\hadoop\common\lib\*;$HADOOP_HOME\share\hadoop\hdfs\*;$HADOOP_HOME\share\hadoop\hdfs\lib\*;$HADOOP_HOME\share\hadoop\mapreduce\*;$HADOOP_HOME\share\hadoop\mapreduce\lib\*;$HADOOP_HOME\share\hadoop\tools\*;$HADOOP_HOME\share\hadoop\tools\lib\*;$HADOOP_HOME\share\hadoop\yarn\*;$HADOOP_HOME\share\hadoop\yarn\lib\*
You can also update your .profile (present in $HOME/.profile) or .kshrc (present in $HOME/.kshrc) to include the HADOOP paths.
That should solve your problem.
Related
While firing this command, it throws an error
hdfs dfs -copyFromLocal /home/osboxes/sample new
copyFromLocal: `new': No such file or directory"
hdfs dfs -ls gives" ls: `.': No such file or directory"
You don't have a HDFS user directory to copy anything into
Verify by hdfs dfs -ls /user | grep $(whoami)
You need to make this folder before you can really do anything useful such as running MapReduce, or copying files into the relative path of the user folder such as you've done
hdfs dfs -mkdir -p "/user/$(whoami)"
hdfs dfs -chown -R $(whoami) "/user/$(whoami)"
Then run your copy command
Or give a different path hdfs dfs -copyFromLocal file /tmp/somePlace
Someone suggest to me, what's the best solution to shipp files from different sources and store them in hdfs based on their names. My situation is :
I have a server that has large number of files and I need to send them to HDFS.
Actually I used flume, in its config I tried spooldir and ftp as sources, but both of them has disadvantages.
So any idea, how to do that ?
Use the hadoop put command:
put
Usage: hadoop fs -put [-f] [-p] [-l] [-d] [ - | .. ].
Copy single src, or multiple srcs from local file system to the destination file system. Also reads input from stdin and writes to destination file system if the source is set to “-”
Copying fails if the file already exists, unless the -f flag is given.
Options:
-p : Preserves access and modification times, ownership and the permissions. (assuming the permissions can be propagated across filesystems)
-f : Overwrites the destination if it already exists.
-l : Allow DataNode to lazily persist the file to disk, Forces a replication factor of 1. This flag will result in reduced durability. Use with care.
-d : Skip creation of temporary file with the suffix .COPYING.
Examples:
hadoop fs -put localfile /user/hadoop/hadoopfile
hadoop fs -put -f localfile1 localfile2 /user/hadoop/hadoopdir
hadoop fs -put -d localfile hdfs://nn.example.com/hadoop/hadoopfile
hadoop fs -put - hdfs://nn.example.com/hadoop/hadoopfile Reads the input from stdin.
Exit Code:
Returns 0 on success and -1 on error.
https://hadoop.apache.org/docs/current/hadoop-project-dist/hadoop-common/FileSystemShell.html#put
I have this pig command executed through oozie:
fs -put -f /home/test/finalreports/accountReport.csv /user/hue/intermediateBingReports
/home/test/finalreports/accountReport.csv is created on local filesystem of only one of the hdfs nodes. I recently added a new HDFS node and this command fails on that hdfs node since /home/test/finalreports/accountReport.csv doesn't exist there.
What is the way to go for this?
I came across this but it doesn't seem to work for me:
Tried the following command:
hadoop fs -fs masternode:8020 -put /home/test/finalreports/accountReport.csv hadoopFolderName/
I get:
put: `/home/test/finalreports/accountReport.csv': No such file or directory
I was trying to unzip a zip file, stored in Hadoop file system, & store it back in hadoop file system. I tried following commands, but none of them worked.
hadoop fs -cat /tmp/test.zip|gzip -d|hadoop fs -put - /tmp/
hadoop fs -cat /tmp/test.zip|gzip -d|hadoop fs -put - /tmp
hadoop fs -cat /tmp/test.zip|gzip -d|hadoop put - /tmp/
hadoop fs -cat /tmp/test.zip|gzip -d|hadoop put - /tmp
I get errors like gzip: stdin has more than one entry--rest ignored, cat: Unable to write to output stream., Error: Could not find or load main class put on terminal, when I run those commands. Any help?
Edit 1: I don't have access to UI. So, only command lines are allowed. Unzip/gzip utils are installed on my hadoop machine. I'm using Hadoop 2.4.0 version.
To unzip a gzipped (or bzipped) file, I use the following
hdfs dfs -cat /data/<data.gz> | gzip -d | hdfs dfs -put - /data/
If the file sits on your local drive, then
zcat <infile> | hdfs dfs -put - /data/
I use most of the times hdfs fuse mounts for this
So you could just do
$ cd /hdfs_mount/somewhere/
$ unzip file_in_hdfs.zip
http://www.cloudera.com/content/www/en-us/documentation/archive/cdh/4-x/4-7-1/CDH4-Installation-Guide/cdh4ig_topic_28.html
Edit 1/30/16: In case if you use hdfs ACLs: In some cases fuse mounts don't adhere to hdfs ACLs, so you'll be able to do file operations that are permitted by basic unix access privileges. See https://issues.apache.org/jira/browse/HDFS-6255, comments at the bottom that I recently asked to reopen.
To stream the data through a pipe to hadoop, you need to use the hdfs command.
cat mydatafile | hdfs dfs -put - /MY/HADOOP/FILE/PATH/FILENAME.EXTENSION
gzip use -c to read data from stdin
hadoop fs -put doesnt support read the data from stdin
I tried a lots of things and would help.I cant find the zip input support of hadoop.So it left me no choice but download the hadoop file to local fs ,unzip it and upload to hdfs again.
I have constructed a single-node Hadoop environment on CentOS using the Cloudera CDH repository. When I want to copy a local file to HDFS, I used the command:
sudo -u hdfs hadoop fs -put /root/MyHadoop/file1.txt /
But,the result depressed me:
put: '/root/MyHadoop/file1.txt': No such file or directory
I'm sure this file does exist.
Please help me,Thanks!
As user hdfs, do you have access rights to /root/ (in your local hdd)?. Usually you don't.
You must copy file1.txt to a place where local hdfs user has read rights before trying to copy it to HDFS.
Try:
cp /root/MyHadoop/file1.txt /tmp
chown hdfs:hdfs /tmp/file1.txt
# older versions of Hadoop
sudo -u hdfs hadoop fs -put /tmp/file1.txt /
# newer versions of Hadoop
sudo -u hdfs hdfs dfs -put /tmp/file1.txt /
--- edit:
Take a look at the cleaner roman-nikitchenko's answer bellow.
I had the same situation and here is my solution:
HADOOP_USER_NAME=hdfs hdfs fs -put /root/MyHadoop/file1.txt /
Advantages:
You don't need sudo.
You don't need actually appropriate local user 'hdfs' at all.
You don't need to copy anything or change permissions because of previous points.
try to create a dir in the HDFS by usig: $ hadoop fs -mkdir your_dir
and then put it into it $ hadoop fs -put /root/MyHadoop/file1.txt your_dir
Here is a command for writing df directly to hdfs file system in python script:
df.write.save('path', format='parquet', mode='append')
mode can be append | overwrite
If you want to put in in hdfs using shell use this command:
hdfs dfs -put /local_file_path_location /hadoop_file_path_location
You can then check on localhost:50070 UI for verification