In NAPT HA(Conntrack based) NAT rules are not programmed when a switch comes back after a failure.

In NAPT HA(Conntrack based) NAT rules are not programmed when a switch comes back after a failure.

Steps to reproduce
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With two computes
1) Create internal n/w external n/w.
2)Create a router and add the internal n/w
3)Set the external n/w as the router g/w
4)Spawn a vm in each compute node.
5)Reboot OVS of the elected NAPT switch.
6)Ping router g/w from the vm in the rebooted ovs

Expected Output
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Ping to router g/w should succeed

Actual Output
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Ping fails.