ACLs stands for Access Control Lists and it gives finer level access control over files. Without ACLs permissions are controlled at owner, group and others levels only. To use ACLs in HDFS, we need to set dfs.namenode.acls.enabled to true as part of hdfs-site.xml. We can use hadoop fs -setfacl to set ACL at file or directory …
ACLs stands for Access Control Lists and it gives finer level access control over files. Without ACLs permissions are controlled at owner, group and others levels only. To use ACLs in HDFS, we need to set dfs.namenode.acls.enabled to true as part of hdfs-site.xml. We can use hadoop fs -setfacl to set ACL at file or directory …
Controlling Access using ACLs – Enable ACLs on Cluster Read More »
Let us go through file permissions in HDFS. As we create the files, we can check the permissions on them using -ls command. Typically the owner of the user space will have rwx, while members of the group specified as well as others have rx We can change the permissions using hadoop fs -chmod We can …
Managing files and file permissions – HDFS File permissions Read More »
Let us see how we can preview the data in HDFS. If we are dealing with files contain text data (files of text file format), we can preview contents of the files using different commands as -tail, -cat etc. -tail can be used to preview last 1 KB of the file -cat can be used …
Managing files and file permissions – previewing data in HDFS Read More »
We can also copy files with in HDFS using commands like cp and mv. hadoop fs -cp to copy files from one HDFS location to another HDFS location hadoop fs -mv to move files from one HDFS location to another HDFS location mv is faster than cp as mv deals with only metadata where as …
We can copy files from local file system and vice versa. We can append data into existing files in HDFS. hadoop fs -copyFromLocal or hadoop fs -put – to copy files from local filesystem and HDFS. Process of copying data is already covered. File will be divided into blocks and will be stored on Datanodes …
Managing files and file permissions – Copying files Local file system and HDFS Read More »
