Hi Vadim
Many thanks for your reply.
"You should configure properly routing tables on EACH node in simulation and container as well..
Also check if packets are not droped on LXC interface."
Each LXC runs OVS and connects to ns-3 node, so I should not run any routing because the nodes are just forwarding devices and the controller is responsible for the routing decisions.
"What technology is used on ns3 between B and C.. ?"
All the nodes are in ad hoc mode.