Re: [libvirt-users] libvirt and NAT on a system that already has a DHCP server

On Thu, Feb 01, 2018 at 09:19:11AM -0500, Laine Stump wrote: > On 01/30/2018 07:37 PM, john(a)bluemarble.net wrote: >> I'm trying to use virt-manager and qemu/kvm on Arch Linux. The box I'm >> using is also the router for my house. It runs a kea DHCP server. When I >> try to start the default NAT network, it can't start dnsmasq because that >> port is already bound. Is there a way to have it not bind on this >> interface? I see there is an except-on statement in the dnsmasq.conf, but >> I can't add lines to that directly, and I didn't see any way to add >> special options using virsh net-edit default. > > The dnsmasq processes run by libvirt to serve dhcp for the virtual > networks already does this - they listen *only* on the bridge created > for their particular network, nothing else. Your problem is that your > host system's dhcp server has been configured to automatically listen on > all interfaces. > > So it's not the configuration of the libvirt network that needs to > change, it's the configuration of the host system's dhcp server. It > needs to be told that it shouldn't automatically listen on all new > interfaces, but to just listen on certain specific interfaces. Checkout this https://wiki.libvirt.org/page/Libvirtd_and_dnsmasq