The IBM Cloud® Object Storage Scanner and Replay prerequisites are listed:

IBM Cloud Object Storage Scanner prerequisite
For the Scanner, you must enable the Get Bucket Extension for all accesser devices.

To enable the Get Bucket Extension, you must set the s3.listing-name-only-enabled equal to true in the Manager System Advanced Configuration.

See Figure 1.
Figure 1. Example of the system advanced configuration
Example of a system advanced configuration
Remember: You do not need to restart the Accesser, but you might need to wait for 5 minutes before the setting takes effect if you do not restart it.
IBM Cloud Object Storage Replay prerequisite
For the Replay, access_logs are uploaded to the management vaults within 1 hour after rotation. Rotation can be triggered earlier by setting the Rotation Period to the minimum value of 15 minutes in Manager under Maintenance/Logs/Device Log Configuration. Refer to the IBM Cloud Object Storage System documentation to make sure that this is configured, and the relevant access logs are present before you run the Replay.