Build#: Lithium-SR1 Build
Openstack: stable/kilo
ODL config (on etc/custom.properties)
===========
ovsdb.of.version=1.3
ovsdb.l3.fwd.enabled=yes

local.conf snip
=======
enable_plugin networking-odl https://github.com/stackforge/networking-odl stable/kilo
Q_PLUGIN=ml2
ENABLE_TENANT_TUNNELS=True
Q_ML2_TENANT_NETWORK_TYPE=vxlan
PUBLIC_INTERFACE=em3
ODL_MODE=compute
ODL_MGR_IP=<ODL_IP>
ODL_LOCAL_IP=<DATA_NET_IP>
ODL_PROVIDER_MAPPINGS=br-ex:<EXT_INT>
disable_service q-l3
Q_L3_ENABLED=True
ODL_L3=True

Openstack setup
=================
eth0 => Mgmt Network eth1=> Data Network eth3 => External Network
1 openstack controller & 3 compute node

Problem:
============
East-West traffic not working in between subnets in specific restack scenario.

Step to Recreate:
===============
1.Router Gateway contains interface of both 1.1.1.x & 2.1.1.x with 8.1.1.1 External Gateway.
2.Spawn 2 VM's each 1.1.1.x & 2.1.1.x network on both compute nodes.
Compute Node1 => VM1: 1.1.1.3 VM3: 2.1.1.3
Compute Node2 => VM2: 1.1.1.4 VM4: 2.1.1.4
3.Associate Floating IP Address on following way
Compute Node1 => VM1: 1.1.1.3 Floating IP : 8.1.1.3
Compute Node2 => VM2: 1.1.1.4 Floating IP : 8.1.1.4

5.Disassociated floating IP,Deleted all VM's spwaned on compute node-2 and un-stacked

6.Restacked and provisioned new VM(s) with private ip on 2.1.1.x network and associated the floating IP address.
Compute Node2 => VM5: 2.1.1.5 Floating IP Address=> 8.1.1.5

Try following test:
1.ping between 2.1.1.5(compute node 2) to 2.1.1.3 (compute node 1) - successful
2.ping between 2.1.1.5 private ip /8.1.1.5-floating ip to 8.1.1.1 (ext Gateway),8.1.1.3(compute node 1 VM) successful
3.ping between 2.1.1.5 (compute node2) to 1.1.1.3 (compute node1) -Unsuccessful.

3rd Test needs to passed via Private IP of VM as well.Since RouterGateway Interface contains 1.1.1.x Network.

Workaround:
==========
Provision new VM on restacked compute node with 1.1.1.x network,then 1.1.1.x network will be reachable from 2.1.1.5 VM

Associated defect #4408,4346