RAID safest magnetic medium for Long Term Archiving?

[spiritG]

Would using Raid drives for long term (10 to 20 years) backup significantly improve the chances that the data fill be fully recoverable that long in the future?
Yes, probably at least two current ProTools systems and computers will be kept to compatibly recover the data.
But if the most likely reason the data wouldn't be recoverable would be bearing failure, will that prevent the second drive in the RAID enclosure from being accessible? And would both likely fail if not used regularly?
Trying to figure out an archive strategy for 10 to 20 years sitting in a moderate, but not clean room environment.

[ekuehnl]

Tape is still the best long-term backup media. I wouldn't expect to get ten years out of hard drives. The jury is still out on optical, although IT pros don't recommend it.

[TimNielsen]

Definitely tape. The real problem with it is that whatever program you used to archive it to tape will probably be long gone by then. Look at all the people who backed up using Mezzo and now can't even find a working copy or authorization diskette (yes it used a diskette for copy protection) to restore that stuff from 10 years ago.

So your best bet would be a combination of all of the above.

My important work gets two hard drive backups, one offsite, and an LTO4 tape backup, or 2 if it's super crucial. Overkill? Probably. But media is cheap now, and some of this stuff is off course priceless were I to lose it.

[Bill Denton]

As just one among many IT pros...

Unless you have a ridiculous amount of data, I'd go with optical storage such as DVD. I'd also pick up a brand new, USB drive matching your audio media and put it away with you're media.

I'm not 100% sure, but I believe that current best practice calls for storing optical media in a tightly closed box with a black interior.

In an IT department, tape is generally only used for relatively short-term storage. You are backing up dynamic storage, and a year-old backup tape is not normally very useful. Also, there are a number of tape autoloaders available which allow for totally automated backup.

So, while tape is the norm in IT departments, for archival storage I would go with optical...

[drenkrom]

I'd go for a combination of storage to be on the safe side for such prolonged archiving.

With optical media being so cheap, it's almost a no-brainer to make a copy to DVD or BD-R. I'm personally wary of optical media archiving, as I've started to get some old copies that can't be read anymore after about 10-12 years of storage. The media was of lesser quality back then, but I still don't fully trust it after seeing it fail firsthand.

Tape is the best long-term archiving medium, IMO. I can still get back sessions backed up in the mid-90s without the slightest hitch. The important thing to do if you go for tape is to keep the backup system exactly as it is now, along with the media. I'm sure glad I kept the Mezzo-running G3 with the original tape drive, a few clones of the system and a stock of replacement parts! I've seen so many people crumble when realizing they got rid of the equipment to access their older archives.

I'd personally be wary of RAID. Hard drive mechanisms seize when unused for prolonged periods. You seem to refer to a two-drive FW RAID enclosure, using mirroring. If you're going to do that, the paranoid archivist in me would recommend two separate drives. A mechanical failure on one drive in the RAID would leave the other accessible, but an interface or controller fault in the enclosure would leave both drives inaccessible. If you go for HDD archiving, they should be spun up once in a while. The jury is still out on SSD for prolonged storage but I don't trust it for archiving, and the prices are rather restrictive anyways.

Basically, when it comes to archiving important material, I think you have to be a bit pessimistic and envision the worst case scenario and go for two or three copies on two distinct systems. When I've stuck to this attitude, everything has always been perfect. Most od the times I was lenient and thought it would all work out, it didn't.

IHTH

[hummerZ]

The only truly robust long-term archival system is one of perpetual (and redundant) migration towards newer standards.

For short to medium-term archiving, large disk arrays with parity/redundancy are a great solution, provided that the system is well-maintained, and that drives are cycled out as needed.

The problem with tape systems (as people have already pointed out) is that they are mostly proprietary, and are phased out far too quickly to be relied upon as a single solution. Your G3/Mezzo/Retrospect system will not be around in 30 years, believe me. For that matter, neither will AIT, LTO, exabyte, etc.

And I agree that for non-enterprise archiving on a budget, the best option at the moment is a combination of optical and hard disk backup.