Same kind of problem here : Running Ubuntu-servers 12.04 VMs on Ubuntu-servers 12.04 using KVM/Libvirt over bridges.
Pinging my gateway from a random VM and watching packets with tcpdump on the kvm host : icmp is ok on my vnet -> ok on the bridge -> ok on my bond (active- backup) -> ok on my gateway (reply) -> ok on my bond -> ok on my brigde -> No packet received on my vnet !!!! brct showmacs mybridge seems to be ok showing my mac:addr (bridge+vm) I have to ifdown/ifup my eth0 on virtual guest to make it work again til the next time. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/997978 Title: KVM images lose connectivity with bridged network To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/bridge-utils/+bug/997978/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs