On 2/25/24 10:34, Jeffrey Walton wrote:
Hi Everyone,
I'm having trouble understanding what I need to do so my VM guests use the DHCP server on my LAN. I've read <https://wiki.libvirt.org/VirtualNetworking.html#virtual-networking>, but I don't see the use case covered. There is a section on dns-dhcp, but it looks like some sort of libvirt-internal setup so guests get their networking params from libvirt, and not my DHCP server.
(I am looking for something similar to VirtualBox and Bridged networking. VBox does what I want when I select a bridged adapter).
How do I set up networking so the VM Guest uses LAN DHCP?
You have basically two options: 1) create a linux bridge (brctl addbr ...) or an OpenVSwitch bridge, plug your eth0 into it and then configure VMs to have their vNICs plugged into the bridge (<interface type='bridge'> <source bridge='...'/> ..). 2) Use macvtap (<interface type='direct'> <source dev='eth0'/> ...). There is a caveat though. While 2) is less labor intensive, it won't allow VMs to talk to each other. For that you'd need a switch with so called hairpin turned on. Michal