When D2D media are expiring and daily IDB maintenance is happening or when 'omnimm -delete_unprotected_media' is run, it could happen that the store is, for whatever reason, not reachable at that time. It could also be we're dealing with immutable data which would prevent the object to get deleted from the store. So the result would be that the object is still available on the store while it would have been deleted from the IDB on the DP side.
The problem described above is the default behavior. This is to ensure expired catalogs do not get stuck on the cell server if the related data cannot be deleted for whatever reason. The downside is that there will be an inconsistency between the IDB and the store. This behavior can be changed by setting the following global parameter:
This way the B2D media will not be exported from the IDB if the corresponding data deletion on the store is failing.
Note that exporting a medium means it will be removed from the IDB and this unrelated to the setting mentioned above. This means that if there is a related object on the store, it will be left there. For this reason, exporting media should be done with care. Either when it is known there is no related object or when the deletion of the object on the store is being done in parallel or when it is really desired to keep the object on the store without a related medium in DP (deliberately introducing the inconsistency).