It looks like this is related to the discussion of vhost_net, packet checksumming and DHCP @ http://www.spinics.net/lists/kvm/msg37660.html and recent changes to libvirt that enable 'vhost=on' by default for KVM processes (vhost=on does not get set by default on precise)
Using iptables on the host with 'vhost=on' to workaround fixes the issue: iptables -A POSTROUTING -t mangle -p udp --dport 68 -j CHECKSUM --checksum-fill Also, disabled vhost explicitly in instance's libvirt.xml does as well, by setting <driver name='qemu'/> in the <interface> section of the domain's configuration. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1035172 Title: DHCP broken for Openstack Nova instances since kernel v3.3 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1035172/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
