I have huge high definition video files on a 2TB external hard drive (and its clone). The external hard drive is maxed out. I would like to move many of the video files to a new 3TB external hard drive (G-drive, and a clone) and leave a sub-group of video files (1+ TB) on the original external hard drive (and its clone).
I am copying files from original external drive ("ext drive A") to new external drive ("ext drive B") via Carbon Copy Cloner (selecting iMovie event by event that I want to transfer). Just a note: I do not know how to partition or make bootable drives, I see suggestions with these steps in them.
1.) I assume this transfer of files will create extreme fragmentation on drive A. Should I reformat/re-initialize ext drive A after moving the files I want? If so, how best to do this? Do I use "Erase" within Disk Utilities? Do I need to do anything else before transfering files back onto ext drive A from its clone?
2.) Do I also need to defrag if I reformat ext drive A? Do I defrag instead of or in addition to reformating? If so, how to do this? I've read on these forums so many warnings and heard too many stories of this going awry. Which 3rd party software to use?
Thank you in advance for any suggestions, tips, advice. This whole process makes me SO nervous.
To your remaining question,
Is ... it better to reformat the drive then copy the files back on from the backup drive? .
I have already answered this.
If you want to rearrange the remaining files (on A) to a contiguous space, you do not have to reformat, instead, you clone fragmented A to B. That makes the B copy contiguous. OK. Then you clone the B back to A which is then also contiguous, The result is a defragmented A.
No reformatting is required to effect this, nor is reformatting a maintenance procedure. Maintenance of the directory structure can be performed by Repair Disk in Disk utility.