LBaaSv2 doesn't program any rules in ovs

Summary
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In beryllium and boron opendaylight releases, the lbaasv2 functionality doesn't work properly. After creation of the load balancer pool with members, there are no flows in openvswtich programmed.

This works properly in lithium-sr4 release.

I tried to debug it and I observed that the neutronLBPoolCache member of the LBaaSPoolMemberHandler is always empty, thus no pool is found for the member to be added to.

To recreate
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create a private network and two instances in it.

Create the Load Balancer (for that you need the VIP port created in neutron)
Create the load balancer pool with the two members.

For that you can use the Postman collection in [1]

in lithium the steps here [0] worked – after pool is created, there is bunch of flow rules in table 50 of the br-int bridge.

It didn't work with beryllium nor boron (no rules in table 50 of the br-int bridge).

[0] https://wiki.opendaylight.org/view/OVSDB_Integration:LBaaS
[1] ovsdb\resources\commons\Neutron-v2.0-LBaaS-API-Examples_July15.json.postman_collection.txt