Hi All I am experimenting with a system comprising Cisco UCS Blades and Nexus 5k switches. I am trying to understand the best way to define network interfaces for my vms, without having to specify exact source device names or PCI addresses, as I want to be able to migrate vms between nodes and not have to worry about namespace or pcispace collisions. At the moment my network definition looks like: <interface type='direct'> <mac address='52:54:00:c0:cb:2a'/> <source dev='eth55' mode='private'/> <virtualport type='802.1Qbh'> <parameters profileid='TestKVMProfile'/> </virtualport> <model type='virtio'/> <driver name='vhost'/> </interface> libvirt added a few extra settings when I added it: <target dev='macvtap0'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> The issue I have with this config is that I am specifying a source dev (eth55), which I would have to keep manual track of across all vms in my infrastructure. Is there a way to use a high-speed virtual network interface, which is created on the fly for the vm, and supports migration cleanly to another kvm host (ie, does not rely on any specific host resource names). Sorry for any confusion caused from my lack of understanding :) Thanks Chris -- Chris Picton Executive Manager: Systems Cell: 082 339 3135 Email: chris(a)nashua-ecn.com Tel: 087 940 0031 Fax: 087 940 0001 Nashua ECN is a Division of Reunert Limited (Reg. No. 1913/004355/06). The contents of this e-mail, which may include one or more attachments, is strictly confidential, and is intended solely for the use of the named recipient(s). If you have received this e-mail in error, you are not permitted to and must not disclose, distribute, or retain it, and are requested to please notify the sender immediately by return e-mail and delete it thereafter.