Hi, I'm having trouble with our ovirt environment, i'm not able to start VMs nor to migrate running ones, i'm getting the following error: libvirtError: error from service: ListActivatableNames: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken. Any idea what causes this error? oVirt (oVirt Engine Version: 3.5.6.2-1.el7.centos) running on: CentOS Linux release 7.2.1511 kernel : 3.10.0-327.4.4.el7.x86_64 Nodes: Red Hat Enterprise Linux Server release 7.2 (Maipo) vdsm-python-4.16.30-0.el7.centos.noarch vdsm-cli-4.16.30-0.el7.centos.noarch vdsm-yajsonrpc-4.16.30-0.el7.centos.noarch vdsm-xmlrpc-4.16.30-0.el7.centos.noarch vdsm-hook-vmdisk-4.16.30-0.el7.centos.noarch vdsm-jsonrpc-4.16.30-0.el7.centos.noarch vdsm-hook-floppy-4.16.30-0.el7.centos.noarch vdsm-python-zombiereaper-4.16.30-0.el7.centos.noarch vdsm-4.16.30-0.el7.centos.x86_64 vdsm-hook-vhostmd-4.16.30-0.el7.centos.noarch Thanks for any hint/help. rgds, Arsène