For those of use who are acronym-challenged, trying to figure out what te DC part of "DC to DR" means, let me offer some explination
When data is backed up, all information about the backup is stored in a Data Catalog Binary File (DCBF). When Protection on a Backup session expires, or the Media is over-written, the DCBF file is ddeleted, and a new DCBF file is created.
If you can get the media out of the way, like move it to an unsused Media Pool, the data on it wil not be over-written unless the user does it manually. However, it is no longer in the Internal Database
To put all information about that media back into the Internal Database, it must be IMported. This creates a new DCBF file. Because Protection may have expired, I always advise that as soon as teh media finishes importing (3-4 hours for a LTO-4 tape), you should go to the Internal Database context, find the imported session(s), right5-click on the session, and pick Change Data Protection. I usually advise that ti be set to Permanent. The media can be recycled later to remove Protection when the media is ready to be reused
The is also a function called IMport Catalog, for when the media is already in teh IDB, but, the catalog has been deleted. This does not do as complete a job as IMport, so I usually recommend, after making sure where the media is, to Export it first, then Import it