This is a list of users that should not be allowed to login to this service. This is really a paranoid check to absolutely ensure an improper setting does not breach your security. A name starting with a '@' is interpreted as an NIS netgroup first (if your system supports NIS), and then as a UNIX group if the name was not found in the NIS netgroup database. A name starting with '+' is interpreted only by looking in the UNIX group database. A name starting with '&' is interpreted only by looking in the NIS netgroup database (this requires NIS to be working on your system). The characters '+' and '&' may be used at the start of the name in either order so the value +&group means check the UNIX group database, followed by the NIS netgroup database, and the value &+group means check the NIS netgroup database, followed by the UNIX group database (the same as the '@' prefix). The current servicename is substituted for %S. This is useful in the [homes] section. valid users no invalid users root fred admin @wheel