<AuthBy SYSTEM> provides authentication with your getpwnam, getgrgid, and getgrnam system calls. On most Unix hosts, that means authentication from the same user database that normal user logins occur from, whether that be /etc/passwd, NIS, YP, NIS+, or the like. It is implemented in AuthSYSTEM.pm. This allows you to hide whether its password files, NIS+, PAM or whatever else might be installed on your system. It is not supported on Windows, or on systems with shadow password files unless Radiator runs with root or other permissions that allow it to access them.

<AuthBy SYSTEM> honours the Group and GroupList check item. These check items can match the numeric or symbolic group number of the primary or any secondary group.

<AuthBy SYSTEM> understands also the same parameters as <AuthBy xxxxxx>. For more information, see Section 3.32. <AuthBy xxxxxx>.