On 03/14/2013 05:49 AM, yue wrote: > hi,all,please look at interface . > actually ,virbr0 is NAT, my program product a vm-xml which is > not standard. it use the way to product bridge interface to product > a NAT interface. > but i want to know if this can work rightly. > > <interface type='bridge'> #"type='network'" > <mac address='00:1a:4a:a8:7a:09'/> > <source bridge='virbr0'/># network='virbr0' > <target dev='vnet0'/> > <model type='virtio'/> > <boot order='3'/> > <alias name='net0'/> > <address type='pci' domain='0x0000' bus='0x00'! slot='0x03' > function='0x0'/> > </interface> I'm not sure I understand your question. Are you wondering if (A) below is functionally the same as (B)? A - <interface type='bridge'> <mac address='00:1a:4a:a8:7a:09'/> <source bridge='virbr0'/> <target dev='vnet0'/> <model type='virtio'/> <boot order='3'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00'! slot='0x03' function='0x0'/> </interface> B - <interface type='network'> <mac address='00:1a:4a:a8:7a:09'/> <source network='default'/> <!-- you had incorrectly said "virbr0" --> <target dev='vnet0'/> <model type='virtio'/> <boot order='3'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00'! slot='0x03' function='0x0'/> </interface> The answer to that question is "Yes, but...". If we assume that libvirt's "default" network has been setup, and that it is using the name "virbr0" for its bridge device (which is almost always true, but only be coincidence), then those two interface definitions will provide the same result. However, if there is no network named "default", or if the default network happened to be defined after some other network was already defined, and so picked a name different from "virbr0" for its bridge device, then (A) either wouldn't work at all, or would result in the guest being connected to the wrong place. Is there some reason you want to use type='bridge' rather than type='network'? (BTW, you may want to subscribe to libvirt-users@xxxxxxxxxx and use it for questions like this. The amount of traffic is much lower, so your question would be less likely to be buried underneath bunches of patch emails) -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list