vfs_acl_xattr man page

vfs_acl_xattr — Save NTFS-ACLs in Extended Attributes (EAs)


vfs objects = acl_xattr


This VFS module is part of the samba(7) suite.

The vfs_acl_xattr VFS module stores NTFS Access Control Lists (ACLs) in Extended Attributes (EAs). This enables the full mapping of Windows ACLs on Samba servers.

The ACLs are stored in the Extended Attribute security.NTACL of a file or directory. This Attribute is not listed by getfattr -d filename. To show the current value, the name of the EA must be specified (e.g. getfattr -n security.NTACL filename).

This module forces the following parameters:

· inherit acls = true

· dos filemode = true

· force unknown acl user = true

This module is stackable.


acl_xattr:ignore system acls = [yes|no]

When set to yes, a best effort mapping from/to the POSIX ACL layer will not be done by this module. The default is no, which means that Samba keeps setting and evaluating both the system ACLs and the NT ACLs. This is better if you need your system ACLs be set for local or NFS file access, too. If you only access the data via Samba you might set this to yes to achieve better NT ACL compatibility.

If acl_xattr:ignore system acls is set to yes, the following additional settings will be enforced:

· create mask = 0666

· directory mask = 0777

· map archive = no

· map hidden = no

· map readonly = no

· map system = no

· store dos attributes = yes

acl_xattr:default acl style = [posix|windows]

This parameter determines the type of ACL that is synthesized in case a file or directory lacks an security.NTACL xattr.

When set to posix, an ACL will be synthesized based on the POSIX mode permissions for user, group and others, with an additional ACE for NT Authority\SYSTEM will full rights.

When set to windows, an ACL is synthesized the same way Windows does it, only including permissions for the owner and NT Authority\SYSTEM.

The default for this option is posix.


The original Samba software and related utilities were created by Andrew Tridgell. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed.


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