We're running kolla train, and we use the AggregateMultiTenancyIsolation for some aggregates by setting filter_tenant_id. Today customers reported build failures when they try to build VMs in a non-filtered region. I am able to duplicate the issue: os server create --image <image> --flavor medium --network private --availability-zone open alberttest1 | 5dd44105-2045-4d53-be43-5f521ddb420b | alberttest1 | ERROR | | <image> | medium | 2022-08-26 18:39:38.977 30 INFO nova.filters [req-342d065a-cd47-4edf-bc4b-3f84b34ab97c 25b53bdb96fb5f9f6e7331d7e03eee0a12c45746a9e8b978858b2140a5275a09 fdcf1553db504c8f82a2b54851a4c262 - 8793b235debf49e6aba6bd1e2bf65360 8793b235debf49e6aba6bd1e2bf65360] Filtering removed all hosts for the request with instance ID '5dd44105-2045-4d53-be43-5f521ddb420b'. Filter results: ['ComputeFilter: (start: 50, end: 50)', 'RetryFilter: (start: 50, end: 50)', 'AggregateNumInstancesFilter: (start: 50, end: 50)', 'AvailabilityZoneFilter: (start: 50, end: 6)', 'AggregateInstanceExtraSpecsFilter: (start: 6, end: 6)', 'ImagePropertiesFilter: (start: 6, end: 6)', 'ServerGroupAntiAffinityFilter: (start: 6, end: 6)', 'ServerGroupAffinityFilter: (start: 6, end: 6)', 'AggregateMultiTenancyIsolation: (start: 6, end: 0)'] Region "open" does not have any properties specified, so the AggregateMultiTenancyIsolation filter should not be active. qde3:admin]$ os aggregate show open|grep properties | properties | This is what we would see if it had the filter active: :qde3:admin]$ os aggregate show closed|grep properties | properties | filter_tenant_id='1c41e088b35f4b438023d081a6f70292,3e9727aaf03e4459a176c28dbdb3965e,f9b4b7dc8c614bb09d66657afc3b21cd,121a5da3dd0b489986908bee7eea61ae,d580ccc4b07e478a9efc2d71acf04cc1,107e14eeda01400988e58f5aac8b2772', closed='true' What could be causing this filter to remove hosts when we haven't set filter_tenant_id for that aggregate?