File systems and permissions

There is no permission in these systems which would prevent a user from reading a file. OpenVMS also uses a permission scheme similar to that of Unix, but more complex. The categories are not mutually disjoint:

File systems and permissions

In order for other users to modify the file system, the root user must explicitly grant them access. Amazon EFS file system objects have a Unix-style mode associated with them.

This value defines the permissions for performing actions on that object, and users familiar with Unix-style systems can easily understand how Amazon EFS behaves with respect to these permissions.

Additionally, on Unix-style systems, users and groups are mapped to numeric identifiers, which Amazon EFS uses to represent file ownership. File system objects that is, files, directories, etc.

File systems and permissions

Amazon EFS uses these numeric IDs to check permissions when a user attempts to access a file system object. The mount command can mount any directory in the file system.

File systems and permissions

The initial permissions mode allows: The root user can also grant other users permissions to write to this directory. Allow users to write to the Amazon EFS file system root. A user with root privileges can grant other users access to the file system.

To change the Amazon EFS file system ownership to a non-root user and group, use the following: When a user attempts to access files and directories, Amazon EFS checks their user ID and group IDs to verify the user has permission to access the objects. Amazon EFS also uses these IDs as the owner and group owner for new files and directories the user creates.

Amazon EFS does not examine user or group names—it only uses the numeric identifiers. These files define the mappings between names and IDs. If a user accesses an Amazon EFS file system from two different EC2 instances, depending on whether the UID for the user is the same or different on those instances, you see different behavior as follows: The user experience when accessing the file system is the same from both EC2 instances.

You might consider managing user ID mappings across EC2 instances consistently. Users can check their numeric ID using the id command, as shown following: In Amazon Linux, the daemon is called rpc. It translates user and group IDs into names, and vice versa. We recommend you turn this process off on your EC2 instances on Amazon Linux the mapper is usually disabled, in which case don't enable the ID mapperas shown following: If a user or group ID is 0, Amazon EFS treats that user as the root user, and bypasses permissions checks allowing access and modification to all file system objects.

As a result, there may be a brief window where a user who had access to a file system object but the access was revoked recently can still access that object.

This means only the root user can change the owner of a file system object. While the root or the owner user can change the owner group of a file system object, unless the user is root, the group can only be changed to one that the owner user is a member of.If you want to see the the permission of a file you can use ls -l /path/to/file command..

For example. ls -l acroread -rwxr-xr-x 1 floppy May 8 acroread.

List of file systems - Wikipedia

The permissions of a file are the first line of defense in the security of a Unix system. The basic building blocks of Unix permissions are the read, write, and execute permissions. Although there are already a lot of good security features built into Linux-based systems, one very important potential vulnerability can exist when local access is granted - - that is file permission based issues resulting from a user not assigning the correct permissions to files and directories.

The following lists identify, characterize, and link to more thorough information on computer file systems..

Home Fileserver: ZFS File Systems

Many older operating systems support only their one "native" file system, which does not bear any name apart from the name of the operating system itself. A file consists of a lot of (extended) attributes. In Unix the core set of attributes are stored in the inode, including the file mode (permissions).

My solution would be to run the commands from command line opened with administrator privileges. To do this, find command prompt, right-click it, and click run with administrator privileges.

Work with Storage and File Systems - Amazon EMR