I have recurrent difficulties with my CalDigit RAID (HDOne, 8x1TB, RAID 5). I have to run Disk Warrior almost daily. I'm told by CalDigit that I have to reformat the RAID, but I always have a lot of projects in mid-completion, so it is tricky to find the time to back up the data so that I can do that.
I thought I heard you say that your projects are unimportant and that a problem like a failing Raid 5 isn't important.
Ok, I know, you didn't really say that, but I'm worried enough about your data that I phrased it as such. Stop what you're doing, go grab a couple of 2-3 TB drives and backup ASAP. A RAID is not a backup - and yes, I've seen two drives die before in a raid. Backup your data, check the integrity of the backup(s), wipe the raid and reformat.
Then transfer the most important project back. Transfer the others while you work on the key one. You could be working without a net here.
I hear you! If only you could see my editing room: I have an LTO3 backup device, quite a few external hard drives, and I use the three internal "extra" hard drive slots to copy the current materials from the RAID.
The problem is - the problem! If my RAID were working properly, I wouldn't need to reformat it, but because it isn't, the process of making backups is incredibly dicey.
The only backup that I totally trust is to LTO tape. When I make an LTO backup of the material from the RAID, my backup software will do a "verify" which reports back that some of the backed up files did not match the originals on the RAID. So I wind up making several "passes" on the LTO tape, just to be sure that I have good copies of everything.
[Jeff Greenberg]"check the integrity of the backup"
Is there a copy utility which verifies the integrity of a backup? I use a couple of dedicated programs to copy and verify my SxS memory card data. My LTO backup software (Retrospect) has verification. But it would be much faster to have verification for all files, copied from the RAID to a hard drive.
First, you could use Apple's Disk Image - It does have a checksum/verification (but I don't believe it does more than verify.)
The second is you might want to try something based on rsync (the underpinnings of what makes carbon copy cloner and Superduper work.) I found this utility while looking for that: http://sourceforge.net/projects/psyncx/