How should I fill DHCP checksums when using openvswitch? I need it as a work-around when running FreeBSD in a kvm/qemu/libvirt VM. The VM is connected to a LXD instance running openwrt with an openvswitch bridge.
I noticed the workaround for linux bridges in the mangle table on the host. Adding a similar rule on the LXC container which runs the DHCP server (dnsmasq) solves the problem:
iptables -t mangle -A OUTPUT -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill. If this is the recommended solution then I think it should be documented.
The rules for linux bridges mentioned above are inserted by code in the following commit: