Thank you, Laine for you time and patience to give me a detailed answer. I missed the interfaceid parameter in the docs, but now I didn't manage to get it working. The docs state: "The Open vSwitch type virtualport accepts two parameters in its <parameters> element - an interfaceid which is a standard uuid used to uniquely identify this particular interface to Open vSwitch (if you do not specify one, a random interfaceid will be generated for you when you first define the interface[...]" This interfaceid doesn't seem to have anything to do with ovsdb values. $ ovs-vsctl find Port 'name=vm_test' _uuid : f0f06327-6fcc-4073-b8c8-3f42944d43ca bond_downdelay : 0 bond_fake_iface : false bond_mode : [] bond_updelay : 0 external_ids : {} fake_bridge : false interfaces : [eb7fad6e-3728-4bf7-b31e-4a1693e2ec4b] lacp : [] mac : [] name : "vm_test" other_config : {} qos : [] statistics : {} status : {} tag : [] trunks : [] vlan_mode : [] The "_uuid" is ovsdb internal id of a record. If you take "interfaces" value for "interfaceid", libvirt will silently create its own new ovs port, with its own new uuid and defining a libvirt guest's interface with a unique uuid in "interfaceid"... Libvirt will create a new ovs port, and the ovsdb-"interfaces" value will be the interfaceid... And I could not find anything specific about this ovsdb/Port/interfaces. Actually, my point was to find a way to control ovs vlans outside libvirt. Since virsh doesn't have capabilities to edit interface's vlan options, the only way to do it is editing domains' xml-configs through virsh-edit, which is a bit tiresome. (By the way, there must be some technical reason(beyond virt-xml-validate) for designing libvirt writing it's own configuration files instead of reading them...) There should be.. There must be a way to do this. Port parameters are ovs authority. If there is no such way, could you, please, tell me the reason. On 11/21/2016 09:46 PM, Laine Stump wrote: