Setting/Modifying File and Directory ACEs

Describes how to set ACEs for files and directories using maprcli commands.

For files and directories, run the hadoop mfs command to set ACEs. When ACEs are set, by default, the corresponding POSIX mode bits are also set. POSIX mode bits for owner and owning group are deduced by evaluating the corresponding ACEs. POSIX mode bits for others is set only if "p" is given as the value for an ACE.

The following table lists the POSIX mode bits that correspond to the access types.

  ACEs POSIX Mode Bits
File readfile r
writefile w
executefile x
Directory readdir r
addchild w
deletechild w
lookupdir x
Note: The POSIX mode bit granting write (w) access to directory is set only if user, role, or group is granted permission for both (addchild and deletechild) access types.

The hadoop command will, by default, set the POSIX mode bits corresponding to the given ACEs, and:

  • Overwrite existing ACE values with new values, if specified, for access types that were previously set.
  • Set ACE values for access types that have not yet been set, if specified.
  • Not modify access types that were not specified with the command, whether they were previously set or are unset.
Warning: Changing the POSIX mode bits using chmod will not change the corresponding ACE setting and may result in different, conflicting permissions to files and directories.