Error when attach LB policy with member was existed

[Bo Tran]

With a Load Balancer and Cluster have 2 members. I was perform with steps:
1. Add all members of Cluster to Load Balancer
2. Create a Load Balancer Policy using above Load Balancer and attach to Cluster.

I was get error message:

2019-12-12 09:38:22.196 46 INFO senlin.engine.event [req-523e786b-a6bf-4246-8162-326e40a114ae ab329678bc60471b9817dda24e9631b5 4e32b4f4693048c6b845fbf545640d2b - - -] GR-test-hihi[e7a9fb8f] CLUSTER_ATTACH_POLICY[dfd4721b] start: dfd4721b
2019-12-12 09:38:29.396 46 ERROR senlin.drivers.sdk [req-523e786b-a6bf-4246-8162-326e40a114ae ab329678bc60471b9817dda24e9631b5 4e32b4f4693048c6b845fbf545640d2b - - -] ConflictException: 409: Client Error
for url: https://host.com.vn:9876/v2.0/lbaas/pools/f78d22f3-e561-48b3-94ef-a67f22cb66e0/members, Conflict: ConflictException: ConflictException: 409: Client Error for url: https://host.com.vn:9876/v2.0/lbaas/pools/f78d22f3-e561-48b3-94ef-a67f22cb66e0/members, Conflict
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas [req-523e786b-a6bf-4246-8162-326e40a114ae ab329678bc60471b9817dda24e9631b5 4e32b4f4693048c6b845fbf545640d2b - - -] Failed in creating lb pool membe
r: ConflictException: 409: Client Error for url: https://host.com.vn:9876/v2.0/lbaas/pools/f78d22f3-e561-48b3-94ef-a67f22cb66e0/members, Conflict.: InternalError: ConflictException: 409: Client Error
for url: https://host.com.vn:9876/v2.0/lbaas/pools/f78d22f3-e561-48b3-94ef-a67f22cb66e0/members, Conflict
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas Traceback (most recent call last):
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas File "/opt/senlin/senlin/drivers/os/lbaas.py", line 317, in member_add
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas subnet_obj.id)
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas File "/opt/senlin/senlin/drivers/sdk.py", line 101, in invoke_with_catch
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas raise parse_exception(ex)
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas File "/opt/senlin/senlin/drivers/sdk.py", line 90, in parse_exception
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas raise senlin_exc.InternalError(code=code, message=message)
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas InternalError: ConflictException: 409: Client Error for url: https://host.com.vn:9876/v2.0/lbaas/pools/f78d22f3-e561-48b3-94ef-a67f22cb66e0/mem
bers, Conflict
2019-12-12 09:38:29.397 46 ERROR senlin.drivers.os.lbaas
2019-12-12 09:38:29.725 46 ERROR senlin.engine.event [req-523e786b-a6bf-4246-8162-326e40a114ae ab329678bc60471b9817dda24e9631b5 4e32b4f4693048c6b845fbf545640d2b - - -] GR-test-hihi[e7a9fb8f] CLUSTER_ATTAC
H_POLICY[dfd4721b] error: Failed in adding node into lb pool

This error appear because in Pool of Load Balancer was existed members of Cluster.

[OpenStack Infra (hudson-openstack)]

Change abandoned by "Erik Olof Gunnar Andersson <email address hidden>" on branch: master
Review: https://review.opendev.org/c/openstack/senlin/+/700762