The issue was clear by looking at nova's logs: tail -f /var/log/kolla/nova/*
2025-06-02 18:36:33.352 7 CRITICAL nova [None req-59c6740a-b87e-4d78-a513-be72a64f8bf3 - - - - - -] Unhandled error: nova.exception.SchedulerHostFilterNotFound: Scheduler Host Filter AvailabilityZoneFilter could not be found.
I was configuring nova-scheduler with a filter that doesn't exist anymore