It seems that the "No Network Filter" filter makes it and now my overcloud node correctly gets the ip Nov 15 18:25:15 director dnsmasq-dhcp[3453]: DHCPDISCOVER(tap9fdd5920-62) 172.23.0.232 56:6f:3d:48:00:3c Nov 15 18:25:15 director dnsmasq-dhcp[1517]: 3907474188 available DHCP range: 172.23.0.241 -- 172.23.0.251 Nov 15 18:25:15 director dnsmasq-dhcp[3453]: DHCPOFFER(tap9fdd5920-62) 172.23.0.232 56:6f:3d:48:00:3c Nov 15 18:25:15 director dnsmasq-dhcp[1517]: 3907474188 client provides name: ostack-ceph0 Nov 15 18:25:15 director dnsmasq-dhcp[1517]: 3907474188 DHCPDISCOVER(br-ctlplane) 56:6f:3d:48:00:3c ignored Nov 15 18:25:15 director dnsmasq-dhcp[1517]: 3907474188 available DHCP range: 172.23.0.241 -- 172.23.0.251 Nov 15 18:25:15 director dnsmasq-dhcp[1517]: 3907474188 client provides name: ostack-ceph0 Nov 15 18:25:15 director dnsmasq-dhcp[3453]: DHCPREQUEST(tap9fdd5920-62) 172.23.0.232 56:6f:3d:48:00:3c Nov 15 18:25:15 director dnsmasq-dhcp[3453]: DHCPACK(tap9fdd5920-62) 172.23.0.232 56:6f:3d:48:00:3c host-172-23-0-232 For clarity it is also to be said that after the upgrade of oVirt and the import of the storage domain where the VM lived before, the network interfaces resulted swapped. So at begin I exchanged vlan assignment for the vnics to have correct behaviour / binding of names. Only thing I also missed is that the definition of ifcg-br-ctlplane was [root@director ~]# cat /etc/sysconfig/network-scripts/ifcfg-br-ctlplane # This file is autogenerated by os-net-config DEVICE=br-ctlplane ONBOOT=yes HOTPLUG=no NM_CONTROLLED=no PEERDNS=no DEVICETYPE=ovs TYPE=OVSBridge MTU=1500 BOOTPROTO=static IPADDR=172.23.0.220 NETMASK=255.255.255.0 OVS_EXTRA="set bridge br-ctlplane other-config:hwaddr=56:6f:3d:48:00:14 -- br-set-external-id br-ctlplane bridge-id br-ctlplane -- set bridge br-ctlplane fail_mode=standalone -- del-controller br-ctlplane -- set bridge br-ctlplane fail_mode=standalone -- del-controller br-ctlplane" [root@director ~]# And so I had also to change other-config:hwaddr=56:6f:3d:48:00:14 in other-config:hwaddr=56:6f:3d:48:00:13 due to the new mac of the eth1 interface being 56:6f:3d:48:00:13 In fact in my first post you can see the macs not matching.... [root@director ~]# ovs-ofctl show br-ctlplane . . . 1(eth1): addr:56:6f:3d:48:00:13 config: 0 state: 0 speed: 0 Mbps now, 0 Mbps max . . . LOCAL(br-ctlplane): addr:56:6f:3d:48:00:14 config: 0 state: 0 speed: 0 Mbps now, 0 Mbps max OFPT_GET_CONFIG_REPLY (xid=0x4): frags=normal miss_send_len=0 [root@director ~]# So after having the correct mac and using "No Network Filter" filter, all seems as before with VDSM MAC Spoof hook. I'm not sure if there is a less open filter accomplishing my needs... Gianluca