[ovs-discuss] failed to put[create][modify]

[Jesse Gross]

On Thu, Jul 3, 2014 at 10:34 PM, Bannai, Vinay <vbannai at paypal.com> wrote:
> Hello Jesse,
>
> We are running a large Openstack deployment with several hundred
> hypervisors running Openstack Havana with OVS. There are currently around
> several thousand VM's running in this environment.
> Here are the details:
>
> root at pxxx:~# ovs-vsctl --version
> ovs-vsctl (Open vSwitch) 2.0.1.32944
> Compiled Jan 28 2014 23:52:12
> root at xxx:~#
>
> Some of the VM's are not reachable. When we further debugged the VM and
> the hypervisor it is running on, we seeing the following messages in
> ovs-vswitchd.log

Can you try the debugging steps that I mentioned in the previous
message (this patch is now merged into master)?

> When we try to do ovs-dpctl dump-flows and grep for the MAC address
> associated with the VMs, we see the flow has action set to drop.
> Tcpdump on the tap interface of the VM' shows that it is sending DHCP
> packets but the ovs bridge is dropping the flow.

This is likely separate because the userspace is calculating the
action to be drop, that's not a kernel communication issue. Are you
sure that this is incorrect, though? These are all IPv6 neighbor
discovery packets maybe they are being dropped by some rule.