Domain Groups and Samba
Samba supports domain groups that allow users who are members of the group to have administrator rights on each PC in the domain. This enables them to add software and configure network settings, among other tasks. In Windows, domain groups also have the ability to join machines to the domain; however, Samba does not support this currently.
The domain admin group parameter specifies users who will have domain administrator rights. The argument is a space-separated list of user names or group names (group names must have an @ sign prefixed). For example:
domain admin group = USER1 USER2 @GROUP