[ovs-discuss] combining Geneve and VXLAN tunnels

[Ben Pfaff]

On Thu, Nov 24, 2016 at 01:13:16PM +0100, Gerhard Stenzel wrote:
> On 11/23/2016 06:57 PM, Ben Pfaff wrote:
> > On Wed, Nov 23, 2016 at 10:35:41AM +0100, Gerhard Stenzel wrote:
> >> On 11/22/2016 11:20 PM, Ben Pfaff wrote:
> >>> On Thu, Nov 17, 2016 at 03:58:25PM +0100, Gerhard Stenzel wrote:
> >>>> I have a setup with three machines with an OVS switch each. 1 and 2 are connected via VXLAN tunnel, 2 and 3 are connected via Geneve tunnel. The OVSs have each an IP address assigned. ping from 1 to 2 works and ping from 2 to 3 works.
> >>>> But trying to ping from 1 to 3 or 3 to 1 does not work, because the packet coming via the Geneve tunnel from 3 is sent to Geneve port instead of to the VXLAN port on 1.
> >>>>
> >>>> tcpdump on 2 looks like this:
> >>>>
> >>>> IP 192.168.124.68.hp-device-disc > 192.168.124.132.6081: UDP, length 50
> >>>> IP 192.168.124.132.37695 > 192.168.124.111.6081: UDP, length 50
> >>>> IP 192.168.124.111 > 192.168.124.132: ICMP 192.168.124.111 udp port 6081 unreachable, length 86
> >>>>
> >>>> Is this working as expected or is this a bug?
> >>>
> >>> We don't know, because you didn't give us information like how the ports
> >>> are set up or what you put in the flow table.
> >>
> >> Thanks for asking. Please let me know if you need any other details ...
> > 
> > It seems reasonable at first glance.
> > 
> > I'd try using "ovs-dpctl dump-flows" and "ovs-appctl ofproto/trace" to
> > figure out what's happening to the packets that are not behaving as
> > expected.
> > 
> 
> Thanks for the suggestion.
> 
> # ovs-dpctl dump-flows
> recirc_id(0),tunnel(tun_id=0x0,src=192.168.124.68,dst=192.168.124.132,ttl=64,flags(-df-csum+key)),in_port(3),skb_mark(0),eth(src=fe:63:c1:68:b8:4f,dst=ff:ff:ff:ff:ff:ff),eth_type(0x0806),arp(sip=10.0.0.68,tip=10.0.0.111,op=1/0xff), packets:2, bytes:84, used:2.370s, actions:2,set(tunnel(tun_id=0x0,dst=192.168.124.111,ttl=64,tp_src=3329,tp_dst=6081,flags(df|key))),1
> 
> (Not sure, if ofproto/trace needs additional input)

I think I understand your report better now.  It seems bizarre, at the
very least.

I guess that this is Open vSwitch 2.3.2, based on the output you've
shown.

Usually, you'd cut and paste the full flow information from dump-flows
into ofproto/trace,
e.g. "recirc_id(0),tunnel(tun_id=0x0,src=192.168.124.68,dst=192.168.124.132,ttl=64,flags(-df-csum+key)),in_port(3),skb_mark(0),eth(src=fe:63:c1:68:b8:4f,dst=ff:ff:ff:ff:ff:ff),eth_type(0x0806),arp(sip=10.0.0.68,tip=10.0.0.111,op=1/0xff)"
in this case.  Otherwise the ofproto/trace output will have limited
usefulness.

I assume that port 1 is the datapath vxlan port?  (Run "ovs-dpctl
show".)