As far as I understand, the interfaces virbr0 and virbr0-nic are created and managed by libvirt.
● 4: virbr0 Link File: /lib/systemd/network/99-default.link Network File: n/a Type: ether State: no-carrier (unmanaged) Driver: bridge HW Address: 52:54:00:0f:26:e6 Address: 192.168.122.1 ● 5: virbr0-nic Link File: /lib/systemd/network/99-default.link Network File: n/a Type: ether State: off (unmanaged) Driver: tun HW Address: 52:54:00:0f:26:e6
However libvirt did not add anything in my netplan folder (also doesn't show up in nmcli or in /etc/network/interfaces). I assume that those interfaces are created and brought up by libvirt upon the starting of the daemon.
So is it good practice not to specify them in netplan or should I add them in my configuration ?
Also, how would, theoretically, the configuration for a natted virtual bridge look like according to netplan ?