Hi I am running a multi-region Ceph cluster with version 18.2.6. Our system has been operating reliably for a long time and currently holds over 100,000 buckets and approximately 1.5 billion objects. We recently attempted to add a new zone to the primary region. To control the synchronization scope, we globally disabled bucket sync using sync disable on all buckets, intending to enable sync selectively only for specific buckets in a bidirectional manner. A Lua script is in place and functioning correctly, issuing a sync disable request via POST whenever a new bucket is created. Despite this setup, we’ve observed that once the new zone was added, data synchronization began across all buckets, including those where sync was explicitly disabled. Upon investigation, we found that a large number of deleted buckets still have existing bucket instances on the master zone with sync flag set to 0. For example, while we have ~100k active buckets, we have over 150k bucket instances. To mitigate this, we manually updated all stale bucket instances using radosgw-admin metadata put to set the sync flag to 8. The change is reflected correctly on the secondary zone, and the metadata synchronization is working as expected. However, the data is still being fully synced for those deleted buckets. An example scenario: • A bucket x was previously created with bucket ID 123456 and later deleted. • A new bucket x is created by a user with a different ID 654321. • Both bucket instances exist: x:123456 and x:654321. • During data sync, it appears the system tries to replicate bucket x regardless of which bucket ID is associated with it. We also attempted to clean up logs by deleting all relevant data sync and full sync logs from the logging pool, and performed datalog trim, but the issue persists. I have two main questions: 1. Why is full data sync still occurring for bucket instances with sync flag set to 8? 2. What is the recommended and safe approach to remove old/stale bucket instances without risking data loss for users? Currently, the sync configuration is set to replicate data between all zones (sync from all), with "log_meta": false and "log_data": true. Looking forward to your insights. Please let me know if further details or logs are needed. Best regards, Ramin