Looks like this has been around since Grizzly:
https://github.com/openstack/nova/commit/b0582603a401b2e71348e9a862b83acc426097df
Looks like this has been around since Grizzly:
https:/ /github. com/openstack/ nova/commit/ b0582603a401b2e 71348e9a862b83a cc426097df