[amoringello]

Naturally, for me to lose all my data on a RAID-1 with two *identical* drives, they would both have to fail at *exactly* the same moment.

Sadly, not so... you may find that with RAID1 that when a single drive fails, the entire box may stop working.

My problem was that one disk would always be Read from for a certain portion of the drive. All reads were good "up to a point" then fail.
It was several days trying to track down why my RAID1 box would auto-disconnect and reconnect in less than a second.
Only certain activities would fail while I was watching so it took quite a while to track down the problem. Don't really know when it started, as the issue was intermittent at first.

Finally by random luck I pulled one drive and got the bad one. The RAID box worked for a little while.
I found a new drive, but it would not mirror from the first. (same brand, same model drive.)
I'm thinking the enclosure might be bad...????

Now I'm out looking for some place that actually sells RAID boxes. None of the stores around here sells anything under $1000 for RAD1 2GB (CRAZY!!!!).

Still, pulled out an old single-bay enclosure to put my new drive into... started backing up the single remaining drive from the RAID to the new drive and the backup failed. So either the old remaining drive now has the same problem or the enclosure is failing on both bays.

Had to back up from my originals.

In short... DO NOT trust that a mirrored RAID will guarantee protection if one disk fails. That second disk might fail before you can back up or might fail during re-sync from the first drive. Or worse, if the enclosure fails the drives may be useless. (As I understand a RAID'd drive cannot necessarily be read on its own)

[tclausen]

Also, while a RAID-1 (if set up right, i.e., with non-identical disks etc) may protect against a disk crash, it will not protect against "stupid user action" such as accidentally removing a file.

Re. disk-crash, a previous poster made the very pertinent comment that most consumer-grade boxes pretending to offer RAID does not really...while a box (I'm looking at you LaCie) may offer RAID-1, what it really means is that it will make the files available if a disk crashes....but it won't re-mirror if you stick in another disk in place of the crashed one.

Thus the adage: RAID is never ever a substitute for backup, but at best a patch for performance.

I'd honestly very much caution against using RAID in lieu of a proper backup strategy.....and that, even if you're not running a datacenter at home.