<para>Note that the machine ID historically is not an
OSF UUID as defined by <ulink
- url="http://tools.ietf.org/html/rfc4122">RFC
+ url="https://tools.ietf.org/html/rfc4122">RFC
4122</ulink>, nor a Microsoft GUID; however, starting with
systemd v30, newly generated machine IDs do
qualify as v4 UUIDs.</para>