---
features:
  - |
    When using the libvirt driver, Nova instances will now get a
    VirtIO-RNG (Random Number Generator) device by default.  This is to
    ensure guests are not starved of entropy during boot time.  In case
    you want to *disallow* setting an RNG device for some reason, it can
    be done by setting the flavor Extra Spec property ``hw_rng:allowed``
    to ``False``.