Re: [libvirt] libvirt: use existing network bridge

Sascha Frey wrote: > Hi, > I met a problem setting up virt-manager and libvirt: > I want to use an existing customized network bridge with libvirt > (I need special iptables rules and a custom DHCP setup). > So I created a network definition file like this: > <network> > <name>NAT</name> > <bridge name='br-nat' /> > </network> > Unfortunately, I'm unable to activate this network, because libvirt > tries to create the bridge `br-nat' and fails, because it already > exists: > # virsh net-start NAT > error: Failed to start network NAT > error: cannot create bridge 'br-nat': File exists > I just want libvirt to attach the guest's tap devices to this existing > bridge. I don't want libvirt to manage the network. > Is there any chance to realize this set-up? > It should work with virt-manager using the graphical wizard. Yes, just don't define a new network. To use existing bridges, you just need to edit your guest XML files to use something like: <interface type='bridge'> <mac address='00:16:3e:4a:f6:89'/> <source bridge='br0'/> </interface> Note that configured bridges should also show up in virt-manager, I believe.