hadoop fs -put command

问题:

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!

回答1:

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 hdfs user has read rights.

Try:

cp /root/MyHadoop/file1.txt /tmp
chown hdfs:hdfs /tmp/file1.txt
sudo -u hdfs hadoop fs -put /tmp/file1.txt /

--- edit:

Take a look at the cleaner roman-nikitchenko's answer bellow.

回答2:

I had the same situation and here is my solution:

 HADOOP_USER_NAME=hdfs hdfs fs -put /root/MyHadoop/file1.txt /

Advantages:

1. You don't need sudo.
2. You don't need actually appropriate local user 'hdfs' at all.
3. You don't need to copy anything or change permissions because of previous points.

回答3:

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

回答4:

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

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