This might be a bit silly, but have you checked your routes?

Regards,
Victor Palma


On Aug 23, 2013, at 6:28 PM, Geraint Jones <[email protected]> wrote:

> Hi
> 
> I have an interesting use case for quantum networking
> 
> This is the example :
> 
> Server A eth0 10.1.1.1 (http proxy) 
> Server B eth0 10.1.1.2 (runs LXC VM's) 
> Server B lxc-br 10.1.2.0/24 (the LXC's get addresses here)
> 
> Server A and B run OSPF so server A knows 10.1.2.0/24 is behind 10.1.1.2. (We 
> have more than just A and B hence the useage of OSPF)
> 
> If I ping 10.1.2.1 from Server A it fails. 
> If I ping Server A from a VM with IP 10.1.2.1 then it works, however looking 
> at the tcpdump the source of the VM's ICMP is rewritten to Server B's eth0 
> address.
> 
> Digging a bit deeper I see this on Server B when pinging from Server A to an 
> LXC
> 
> tcpdump -i eth0 host 10.1.2.1
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
> 13:49:52.850764 IP 10.1.1.1 > 10.1.2.1: ICMP echo request, id 25672, seq 387, 
> length 64
> 13:49:52.850878 IP 10.1.2.1 > 10.1.1.1: ICMP echo reply, id 25672, seq 387, 
> length 64
> 13:49:53.850600 IP 10.1.1.1 > 10.1.2.1: ICMP echo request, id 25672, seq 388, 
> length 64
> 13:49:53.850710 IP 10.1.2.1 > 10.1.1.1: ICMP echo reply, id 25672, seq 388, 
> length 64
> 
> And this is what I see on Server A
> 
> tcpdump -i eth0 icmp
> tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
> listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes
> 13:53:41.852613 IP 10.1.1.1 > 10.1.2.1: ICMP echo request, id 25672, seq 616, 
> length 64
> 13:53:42.852603 IP 10.1.1.1 > 10.1.2.1: ICMP echo request, id 25672, seq 617, 
> length 64
> 
> So the ICMP is getting to the VM without being rewritten, and the reply is 
> being sent to Server A but something is dropping it in transit - I suspect 
> its Open vSwitch GRE...
> 
> If anyone can shed any light on this and if there is something I can do to 
> stop this that would be awesome, We have been doing the on AWS however we 
> have had to create GRE tunnels there inside the instances to make it work, We 
> would love it if we didnt have to do that :)
> _______________________________________________
> Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
> Post to     : [email protected]
> Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack

_______________________________________________
Mailing list: http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack
Post to     : [email protected]
Unsubscribe : http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack

Reply via email to