Daan, Please cherry-pick below commit in 4.4-froward in 4.4.
commit 9e4e62466a8c3d00ab5381d7ebfeb70466192a55 Author: Murali Reddy <muralimmre...@gmail.com> Date: Thu Jun 12 13:50:01 2014 +0530 CLOUDSTACK-6755: [OVS] Can't create more than 7 GRE tunnel networks in xen cluster XenServer does not create a bridge automatically when VIF from domU is connected to internal network. So there is logic to force bridge creation by creating VIF in dom0 connected to GRE tunnel network. But there is no logic to delete the VIF after bridge gets created. So this fix ensure VIF is delted when atleast there is one domU VIF connected to the network.