The OpenStack Compute cloud will wait for 24 hours before making changes permanent. This gives you a chance to test things and go back to the old flavor if needed. It is up to you if you want to confirm the resize, the OpenStack Compute cloud will do it anyway after 24 hours, but if you are happy, you can do it by sending a POST request to /servers/id/action. The id parameter is the numeric ID of the server you resized.
Don't forget the JSON payload:
{
"confirmResize": null
}
If you want to use curl, the server resize request would look like this:
$ curl -s -X POST -H "X-Auth-Token:999888777666" -d '{"confirmResize": null}' http://localhost:8774/v1.1/openstack/servers/3/action
