current setup with c-vol in controller and compute:

Oct 21 19:31:53.879222 np87be28cf22444 watcher-decision-engine[93381]: DEBUG urllib3.connectionpool [None req-e855c4ed-65cb-4161-bcbd-935d145e7359 None None] https://10.210.64.225:443 "GET /volume/v3/scheduler-stats/get_pools?detail=True HTTP/1.1" 200 1527 {{(pid=93381) _make_request /opt/stack/data/venv/lib/python3.12/site-packages/urllib3/connectionpool.py:475}}
Oct 21 19:31:53.880167 np87be28cf22444 watcher-decision-engine[93381]: DEBUG keystoneauth.session [None req-e855c4ed-65cb-4161-bcbd-935d145e7359 None None] RESP: [200] Connection: close Content-Length: 1527 Content-Type: application/json Date: Tue, 21 Oct 2025 19:31:53 GMT OpenStack-API-Version: volume 3.0 Server: Apache/2.4.58 (Ubuntu) Vary: OpenStack-API-Version x-compute-request-id: req-6ee524ae-a351-4169-b221-ab0ded22f558 x-openstack-request-id: req-6ee524ae-a351-4169-b221-ab0ded22f558 {{(pid=93381) _http_log_response /opt/stack/data/venv/lib/python3.12/site-packages/keystoneauth1/session.py:613}}
Oct 21 19:31:53.880588 np87be28cf22444 watcher-decision-engine[93381]: DEBUG keystoneauth.session [None req-e855c4ed-65cb-4161-bcbd-935d145e7359 None None] RESP BODY: {"pools": [{"name": "np87be28cf22444@lvmdriver-1#lvmdriver-1", "capabilities": {"pool_name": "lvmdriver-1", "total_capacity_gb": 28.5, "free_capacity_gb": 28.5, "reserved_percentage": 0, "location_info": "LVMVolumeDriver:np87be28cf22444:stack-volumes-lvmdriver-1:thin:0", "QoS_support": false, "provisioned_capacity_gb": 0.0, "max_over_subscription_ratio": "20.0", "thin_provisioning_support": true, "thick_provisioning_support": false, "total_volumes": 1, "filter_function": null, "goodness_function": null, "multiattach": true, "backend_state": "up", "allocated_capacity_gb": 0, "cacheable": true, "volume_backend_name": "lvmdriver-1", "storage_protocol": "iSCSI", "vendor_name": "Open Source", "driver_version": "3.0.0", "timestamp": "2025-10-21T19:31:26.378219"}}, {"name": "np47ad865b91dc4@lvmdriver-1#lvmdriver-1", "capabilities": {"pool_name": "lvmdriver-1", "total_capacity_gb": 28.5, "free_capacity_gb": 28.5, "reserved_percentage": 0, "location_info": "LVMVolumeDriver:np47ad865b91dc4:stack-volumes-lvmdriver-1:thin:0", "QoS_support": false, "provisioned_capacity_gb": 0.0, "max_over_subscription_ratio": "20.0", "thin_provisioning_support": true, "thick_provisioning_support": false, "total_volumes": 1, "filter_function": null, "goodness_function": null, "multiattach": true, "backend_state": "up", "allocated_capacity_gb": 0, "cacheable": true, "volume_backend_name": "lvmdriver-1", "storage_protocol": "iSCSI", "vendor_name": "Open Source", "driver_version": "3.0.0", "timestamp": "2025-10-21T19:31:28.280719"}}]} {{(pid=93381) _http_log_response /opt/stack/data/venv/lib/python3.12/site-packages/keystoneauth1/session.py:648}}


new proposal in with two backends in controller:

Oct 22 08:32:03.663575 np6144f3e50f784 watcher-decision-engine[92981]: DEBUG urllib3.connectionpool [None req-89db0006-10b9-4cae-b280-98c36f9c28c8 None None] https://158.69.70.92:443 "GET /volume/v3/scheduler-stats/get_pools?detail=True HTTP/1.1" 200 1527 {{(pid=92981) _make_request /opt/stack/data/venv/lib/python3.12/site-packages/urllib3/connectionpool.py:475}}
Oct 22 08:32:03.664337 np6144f3e50f784 watcher-decision-engine[92981]: DEBUG keystoneauth.session [None req-89db0006-10b9-4cae-b280-98c36f9c28c8 None None] RESP: [200] Connection: close Content-Length: 1527 Content-Type: application/json Date: Wed, 22 Oct 2025 08:32:03 GMT OpenStack-API-Version: volume 3.0 Server: Apache/2.4.58 (Ubuntu) Vary: OpenStack-API-Version x-compute-request-id: req-94429051-16a7-4698-8d96-302be717fe84 x-openstack-request-id: req-94429051-16a7-4698-8d96-302be717fe84 {{(pid=92981) _http_log_response /opt/stack/data/venv/lib/python3.12/site-packages/keystoneauth1/session.py:613}}
Oct 22 08:32:03.664595 np6144f3e50f784 watcher-decision-engine[92981]: DEBUG keystoneauth.session [None req-89db0006-10b9-4cae-b280-98c36f9c28c8 None None] RESP BODY: {"pools": [{"name": "np6144f3e50f784@lvmdriver-1#lvmdriver-1", "capabilities": {"pool_name": "lvmdriver-1", "total_capacity_gb": 28.5, "free_capacity_gb": 28.5, "reserved_percentage": 0, "location_info": "LVMVolumeDriver:np6144f3e50f784:stack-volumes-lvmdriver-1:thin:0", "QoS_support": false, "provisioned_capacity_gb": 0.0, "max_over_subscription_ratio": "20.0", "thin_provisioning_support": true, "thick_provisioning_support": false, "total_volumes": 1, "filter_function": null, "goodness_function": null, "multiattach": true, "backend_state": "up", "allocated_capacity_gb": 0, "cacheable": true, "volume_backend_name": "lvmdriver-1", "storage_protocol": "iSCSI", "vendor_name": "Open Source", "driver_version": "3.0.0", "timestamp": "2025-10-22T08:31:34.913849"}}, {"name": "np6144f3e50f784@lvmdriver-2#lvmdriver-2", "capabilities": {"pool_name": "lvmdriver-2", "total_capacity_gb": 28.5, "free_capacity_gb": 28.5, "reserved_percentage": 0, "location_info": "LVMVolumeDriver:np6144f3e50f784:stack-volumes-lvmdriver-2:thin:0", "QoS_support": false, "provisioned_capacity_gb": 0.0, "max_over_subscription_ratio": "20.0", "thin_provisioning_support": true, "thick_provisioning_support": false, "total_volumes": 1, "filter_function": null, "goodness_function": null, "multiattach": true, "backend_state": "up", "allocated_capacity_gb": 0, "cacheable": true, "volume_backend_name": "lvmdriver-2", "storage_protocol": "iSCSI", "vendor_name": "Open Source", "driver_version": "3.0.0", "timestamp": "2025-10-22T08:31:51.438688"}}]} {{(pid=92981) _http_log_response /opt/stack/data/venv/lib/python3.12/site-packages/keystoneauth1/session.py:648}}