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Hello everyone, 
I have checked on Mr. Google but the only thing I found was to add  "allow_same_net_traffic "True" and now I can ping between the two hosts, however if I try to ping from the router I get not response from the machine. example:

sudo ip netns exec qrouter-c998da7a-d22f-4b8a-992e-b040a086bdad ping 10.0.0.3

this is using name spaces as you can see (the machine is on Ubunto 12.4)  I have also found that if I create a new security group where I allow ICMP then the router will respond to the ping. So can someone suggest what to look at?

Thank you so much, 

Remo