Optionally use the user name mapping feature to define a mapping of NT user names (or domain names) to UNIX user names. For example, you could map the NT user names administrator and admin to the UNIX user name root. The mapping can be either one-to-one or many-to-one.
Samba supports the creation of ACEs with NT user names that are mapped to UNIX user names.
To continue the example above, you could create an ACE for the administrator user on the NT client and, on the Samba server, the ACE would be created for the root user. The client will display the corresponding ACE as being for the root user, not the administrator user.
If you add an ACE for one user name, like administrator and then display the list of ACEs and see a new ACE for a different user name (root), it maybe confusing. As many NT user names can be mapped to one UNIX user name, Samba only displays the one UNIX user name. It cannot display the NT name that was mapped to the UNIX user name.