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man pages section 8: System Administration Commands

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Updated: Thursday, June 13, 2019

vfs_nfs4acl_xattr (8)


vfs_nfs4acl_xattr - ACLs as NFS4 encoded blobs in extended attributes


vfs objects = nfs4acl_xattr


System Administration tools                               VFS_NFS4ACL_XATTR(8)

       vfs_nfs4acl_xattr - Save NTFS-ACLs as NFS4 encoded blobs in extended

       vfs objects = nfs4acl_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/xattrs). This enables the full mapping of
       Windows ACLs on Samba servers.

       This module is stackable.

       nfs4acl_xattr:encoding = [ndr|xdr]
           This parameter configures the marshaling format used in the ACL
           blob and the default extended attribute name used to store the

           When set to ndr (default) - store the NT ACL with POSIX draft NFSv4
           compatible NDR encoding. By default this uses the extended
           attribute "security.nfs4acl_ndr".

           When set to xdr - store the NT ACL in a format similar to NFS 4.1
           RFC 5661 in XDR encoding. The main differences to RFC 5661 are the
           use of ids instead of strings as users and group identifiers and an
           additional attribute per nfsace4. By default this encoding stores
           the blob in the extended attribute "security.nfs4acl_xdr".

       nfs4acl_xattr:version = [40|41]
           This parameter configures the NFS4 ACL level. Only 41 fully
           supports mapping NT ACLs and should be used. The default is 41.

       nfs4acl_xattr:default acl style = [posix|windows|everyone]
           This parameter determines the type of ACL that is synthesized in
           case a file or directory lacks an ACL extended attribute.

           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

           When set to everyone, an ACL is synthesized giving full permissions
           to everyone (S-1-1-0).

           The default for this option is everyone.

       nfs4acl_xattr:xattr_name = STRING
           This parameter configures the extended attribute name used to store
           the marshaled ACL.

           The default depends on the setting for nfs4acl_xattr:encoding.

       A directory can be exported via Samba using this module as follows:

                 vfs objects = nfs4acl_xattr
                 path = /foo/bar

       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.

       See attributes(7) for descriptions of the following attributes:

       |Availability   | service/network/samba |
       |Stability      | Volatile              |
       This software was built from source available at
       https://github.com/oracle/solaris-userland.  The original community
       source was downloaded from

       Further information about this software can be found on the open source
       community website at http://www.samba.org/.

Samba 4.9.3                       01/24/2019              VFS_NFS4ACL_XATTR(8)