[Users] ComputeNode installation failed ovirt 3.3

Hi, we have successfully deployed ovirt engine 3.3. However, when adding a node based on ovirt node 2.6.1. we get the following error after registration completed successfully and we try to activate the host via webadmin: "Installing Host server4 Starting vdsm" "Host server4 Installation failed. Unexpected connection termination." I attached an excerpt from the engine.log, which shows that an ssh commands fails, but I don't know why. manual ssh connections to the node from the management node work just fine. The node has the IP 10.0.1.4 in the log. Any help would be appreciated. Regards Sven PS: The same Node works fine with oVirt management 3.2. We then did use the "reinstall" feature from the node iso to redeploy the node to the management 3.3 server.