If the replication is triggered when the calculation of metadata on YUM/Debian repository is running then the indexes temporary folders ( _tmp for YUM, _temp for Debian) are being replicated also.
Steps to reproduce:
1. Create a replication with event base replication enabled on a YUM repository.
2. Run calculation on the repository.
3. While the calculation is running, deploy a new artifact to the YUM repository. Now the replication will be triggered and the _tmp folders will be replicated also.
Workaround for this issue:
1. Check the checkbox for Sync Deletes in the replication tab. This will delete all the folders in the destination Artifactory that were removed in the source Artifactory also. Please note, that this will remove artifacts that were deleted also.
2. Use the plugin for clean-up an empty folders from our public GitHub repository: https://github.com/JFrogDev/artifactory-user-plugins/blob/master/cleanup/deleteEmptyDirs.groovy