Cannot start VM with error “no network with matching name ‘default'”

I update libvirt version and want to start VM with the new libvirt tools but I failed as follows. > sudo virsh start kvm1 error: Failed to start domain kvm1 error: Network not found: no network with matching name ‘default’ It seems that the default ‘virbr0’ is missing after I update libvirt so I solve […]