如遇到put: Permission denied: user=root, access=WRITE, inode="/":hdfs:supergroup:drwxr-xr-x
执行
sudo -u hdfs hadoop fs -mkdir /user/root
groupadd supergroup
usermod -a -G supergroup root
su - hdfs -s /bin/bash -c "hdfs dfsadmin -refreshUserToGroupsMappings"