On Tue, Sep 1, 2015 at 4:56 PM, Ben Pfaff <b...@nicira.com> wrote: > I think I've come across a bug in OVS native tunneling, or at any rate > an important difference between Linux kernel and OVS native tunneling. > In Linux kernel tunneling, a tunnel packet received by the kernel first > passes through the kernel IP stack. Among other things, the IP stack > drops packets that are not destined to the current host. It appears to > me that the native tunneling code doesn't have any similar check, > because I'm seeing it accept and packets flooded by the upstream switch > that are not destined to an IP address of the host. This means in > effect that the user of native tunneling must set "options:local_ip", > whereas a user of Linux kernel tunneling doesn't (and probably > shouldn't). > Right. Its bug.
> I suspect that this behavior is unintentional; it isn't mentioned in > README-native-tunneling.md or (as far as I can tell) anywhere else. > > I noticed this while testing OVN. If you configure a few hypervisors > and send packets from only one of them, then the switch that connects > them will flood all the packets to all of the rest (since it hasn't yet > learned where they are). The result is that for N hypervisors, remote > VIFs get N-1 copies of the packets instead of just one. I'm appending a > patch that works around it, though I'd prefer to fix the tunneling code > rather than apply this patch. > We can fix it adding the local ip-address to tnl-port-map. I will send a patch. _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
