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"Earth Crisis" - a Beautiful Short Film Featuring the Music of Dirty Projectors

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NetworkKed1/10/2021 9:41:11 pm PST

re: #128 Charles Johnson

Getting a RAID backup system tomorrow. Four drive bays.

When my main desktop Mac Pro died spectactularly I thought I was doing nightly image backups of the startup disk. Every time I checked the logs it seemed to be running fine, storing the backup on an external USB drive.

But when I set up the replacement Mac Pro, I discovered this backup had not actually completed normally since July of last year. I still don’t know exactly why this happened but I’ll find out.

What makes it worse is that this catastrophic hardware failure apparently happened when some disk operations were under way, or cached incompletely or something, because when I swapped the dead computer’s startup disk into the new machine it started up fine, but I quickly discovered that things were not really fine, and the files affected were the ones I had been working on when the meltdown occurred.

Anyway, I’ve managed to rebuild everything after a lot of work and head-scratching. The drives weren’t harmed, just some data corruption.

I really hate having backups that aren’t really backups. It’s happened to me more than once because of weird hardware crashes. But that’s why I’m going the RAID route now, so the backup can be an automatic virtual mirror image.

Of course, when the meteor hits all this will be meaningless anyway, but til then I’m backed up.

Charles, RAID is not a backup. Everything that goes wrong on one disk, will go wrong on the parity/mirror/redundant disks. It’s useful for redundancy in the face of disk failure (and I’m not telling you it’s worthless, or not to get it), but what you really need is backup *software* that will save multi-layered, multiple days/weeks/months of backups onto that redundant disk target.

I don’t know the Mac world, at all. On PC, Veeam or Acronis (or maybe Backup Exec, though I haven’t seen it in a few years) will do the trick, giving you drive-image backup, good logging, and solid incremental/differential backups that can hold many layers of backup on one device.

You probably know this, but just in case you don’t, I wanted to put this out there. I’ve had to deal with a dozen different clients over the last 25 years who got sold RAID and figured that was all the backup they needed. (“Your sales dude said the second drive kept a copy of my data!” “Yeah, it’s a perfect mirror image of a corrupted drive.”) Not fun for anyone.