In my liberty openstack environment any windows instance we spin up has networking issues. Sometimes it will ping for a few tries, then drop off after a while, sometimes it starts up with no network access. The instance can ping openstack, and also the external gateway (physical router) but that's all.
I have tried adjusting the MTU as mentioned elsewhere to no avail and this has happened on two separate liberty installs.
Any guidance you can provide is greatly appreciated.