Hello,
Short story - cannot receive ipv6 packets in a KVM guest using SR-IOV interfaces (VF), but, ipv4 works fine.
Long Story:
Have 2 KVM VMs set up on 2 separate hosts. OS in the host and the guest is RHEL6.4. The hosts use the 82599 NICs. Have assigned a VFs to each guest (eh4/eth5) using unique mac addresses in the XML guest definition (the other interfaces in the VM are bridged interfaces). Assigned a unique VLAN to each VF per VM (eth4 is 610, eth5 is 611) using 'ip link set' commands. Using Intel provided driver ixgbe (3.15.1) on the host and ixgbevf (2.8.7) in the guest. Plumbed ipv4 and ipv6 IP in the guests for eth4 on each VM. Ping (ipv4) works fine. We can see the packet enter the NIC on the receive side host (tcpdump) and can see it in the guest too. When we repeat the process for ipv6, it fails. It leaves the guest fine, we see it hit the NIC on the received host), but it is NOT received by the guest across the VF. If we pull out the VFs and replace with bridges, ipvv6 works fine so it's not a routing/network issue.
Is there something we need to set up/configure to get ipv6 to show up in the guest?? Note we can also ping out successfully to the upstream L3 switch (subnet gateway), but not to the other VM.
Thanks,
Shawn