files authorized_macs {
    # The default key attribute to use for matches.  The content
    # of this attribute is used to match the "name" of the
    # entry.
    key = "%{Calling-Station-ID}"

    usersfile = ${confdir}/authorized_macs

    #  If you want to use the old Cistron 'users' file
    #  with FreeRADIUS, you should change the next line
    #  to 'compat = cistron'.  You can the copy your 'users'
    #  file from Cistron.
    #compat = no
}

1A:2B:3C:4D:5E:6F
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

1a:2b:3c:4d:5e:6f
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

1A2B3C4D5E6F
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

1a2b3c4d5e6f
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

1A-2B-3C-4D-5E-6F
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

1a-2b-3c-4d-5e-6f
    Reply-Message = "Device with MAC Address %{Calling-Station-Id} authorized for network access"

[...] -- line 777
(0) pap: WARNING: No "known good" password found for the user.  Not setting Auth-Type
(0) pap: WARNING: Authentication will fail unless a "known good" password is available
(0)     [pap] = noop
(0)   } # authorize = ok
(0) ERROR: No Auth-Type found: rejecting the user via Post-Auth-Type = Reject
(0) Failed to authenticate the user
(0) Using Post-Auth-Type Reject
[...] -- line 783