Unstack and restack existing same compute unable to communicate the existing network VM's

Build#: Lithium-SR1 Build
Openstack: stable/kilo

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

Environment
============
Openstack controller & compute node connected with ODL as external mode.

Problem:
========
1.Create network on 2.1.1.0/24
2.Spawned VM1 on compute node 1,VM2 on compute node 2 (with 2.1.1.x network)
3.Unstacked the compute node2
4.Restacked the compute node2
5.Spwaned VM3 on compute node 2 (with 2.1.1.x network)
6.VM3 (on compute node 2) unable to ping VM1 (on compute node 1)
7.Spawned VM4 on compute node 1 (with 2.1.1.x network)
8.VM4(on compute node 1) will able ping VM3 (on compute node 2)
9.VM4(on compute node 1) will able ping VM4 (on compute node 1)

Additional Observation
=====================
Bridge br-int doesnot removed the "vxlan-20.1.1.3",when unstacking the compute node.
============SNIP of sudo ovs-vsctl show===================
Bridge br-int
Controller "tcp:10.16.148.232:6653"
is_connected: true"vxlan-20.1.1.3"
fail_mode: secure
Port "vxlan-20.1.1.3"
Interface "vxlan-20.1.1.3"
type: vxlan
options:

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This stale entries doesn't retained until restack openstack other nodes.