A Word of Warning: Never copy B2D data files with Explorer - unless preparing for a DR situation (or a server migration) against the media server itself. As such Kiran's answer is a better answer than RahulGs
i.e. If you want to store backup data on a USB disk then you should put the b2d device on that USB disk and write the data directly to there with Backup Exec (either as a direct job or a duplicate)
If you copy b2d data around using Explorer and the run the inventory abnd catalog operations on media server that has been in use (so the database is not empty) then the existing b2d inventory in that database can cause problems.
There are at least two scenarios with Backup Exec that can cause problems relating to this.
Scenario 1
You backup to a fixed disk drive and regularly copy the b2d folder to a drive on a remote server or a USB disk using explorer.
Backup Exec continues to write new data into the b2d folder and eventually overwrites some of the files you copied meaning the BKF and IMG folder names are the same but their content is changed. You then need to do a restore from something you manually copied away so you copy this B2D data back into a new B2D folder on the media server and then attenpt to inventory and catalog it.
This will either result in a conflict of two media with same name on the server, or if you thought of that and termporariliy removed the newer versions you will have problems as the content of the Backup Exec database maintains media familes and indexes that are aware of the state of the newest version of the media.and having the older version supplied results in inconsistent information.
Scenario 2
You backup to a fixed disk drive and regularly copy the b2d folder to a drive on a different media server using explorer. However this media server runs it's own jobs.
Because this media server has almost certainly used the same bkf and img names already you get the same conflicts mentioned in scenario one.
Explanation:
Think of Backup Exec as being a very large relational database with 1 part inside the Backup Exec SQL Database, 1 part on the catalogs and one part actually being the media (BKF, IMG, OST, Tape)
Make any part of that inconsistent compared with the other two parts and you will have problems.
As such you can only reliably catalog copeid bkf and img media in the following situations
1) On the original media server when that media has not been used by later jobs
2) If later jobs have used the media, then on the original media server when every piece of media in that media family has been deleted from Backup Exec (not a good idea if the media your are deleting contains newer data that you might also need at some point)
3) In a DR Situation where a media server contains a brand new empty database
Note for a Full DR sitution your best option to remain consistent is
1) Make the Backup Exec Databse maintenance run after all your daily backup jobs finish.
2) Copy or backup the BEDB.bak created by the database maintenance, the rest of the data directory and the existing catalog folder and all your b2d locations to a secondary location.
3) Be prepared to put all this information back if yiou have a disaster.
