Best Way to Back up Music Library

[krutsch]

(05-06-2015 11:57)simoncn Wrote:  

(04-06-2015 23:53)DavidHB Wrote:  That's not exactly the way it works. There are different sorts of RAID arrays, but the concept of true RAID is that, if a disk fails, the rest of the multi-disk system contains the wherewithal to reconstruct the contents of the failed disk on the replacement. In effect, the array repairs itself. This reconstruction is of the whole data structure, rather than of individual files, and it tends to take a long time, which is a significant disadvantage. For a fuller and more technical description, see this Wikipedia article.

This is true for a drive hardware failure but cannot protect against any other causes of file corruption such as software problems or human error.

RAID arrays tend to operate at the block level, as opposed to the entire disc. They "scrub" in the background to detect questionable blocks, sectors and/or tracks and will reallocate those elements and rebuild from the remaining data + parity. There is also the drive's internals SMART data which can provide hints to the RAID system, but in my experience in the storage industry, once a SMART trigger occurs, the whole drive is near death anyway. I use a Drobo RAID device for primary storage, because of its scrubbing function that will detect bit-rot, as well as provide maximum warning for failing drives.

What Simon states is most important: the vast majority of data loss comes from human and software errors - by an order of magnitude. So, any backup strategy must protect you from human errors that go undetected for a relatively long period of time.

Buy three, cheap external drives and rotate your backups between the three of them, always keeping one drive with a relatively old copy in a safe place. Considering the time, money and effort that goes into your music collection, and how cheap 1TB drives are, this is money well spent.

See this link for a backup rotation scheme that works well; it's written from the perspective of tapes, but works for external disks, as well.

http://en.wikipedia.org/wiki/Backup_rota...father-son