[libvirt] Using Libvirt to change the bridge a virtual network card of a running vm is connected to

[Laine Stump]

On 01/20/2012 11:05 AM, Ralf Spenneberg wrote:
> Hi there,
>
> we are using libvirt to manage our VMs. We have several VMs connected to
> different bridges on the same physical KVM host. We need to change the
> bridge a virtual machine is connected to once in a while. Currently we
> are just using brctl to do that. Since this needs to be done over the
> network we would like to use the Libvirtd. Currently this does not seem
> possible. We have not found any interface or function within the libvirt
> library to implement this in a live VM. Only shutdown VMs may be changed
> via editing the XML representation.

One way to do this would be to detach the network device, then reattach 
it with the configuration changed. Of course this would result in the 
guest seeing its network device disappear, then re-appear again, which 
is probably not what you want (although it's still a bit better than 
shutting down the entire guest).