Re: [ARSCLIST] Is recording to Reel-to-reel still the preferred preservation method?

[Ron Fial <ron@xxxxxxxx>]

Regarding the use of hard-drives for archival storage:

I have had considerable experience deploying and servicing hard drives over the last 25 years, starting with platters that were 14-inches in diameter.  I use Mitsui gold CD-Rs for archival storage, I do not rely on hard drives.

I would not recommend leaving any hard drive sitting un-powered for more than a few months.  Regular rotation is desirable to keep a distributed lubricant coating on the drive bearings and wipe away any rust/corrosion products that are beginning to form -- this keeps the polish on the bearings.  It also distributes the platter's surface-lubricant coating to decrease the chances of the motor freezing on startup due to head-to-surface sticking-friction ('stiction').  If a drive has been unused for some time, be sure to bring it up to room temperature for a hour or so before starting it up, or even for a day or so if the drive was stored at a cold temperature (e.g. garage in winter).  Run it for 10 minutes before using, preferably an hour after its operating temperature stabilizes.  The drive will self-calibrate during this period.

There is no way that occasional 'reading' of the data will protect against self-erasure.  The best way to keep the drive readable is to re-write all data every six months. Ideally, you should 'image' the drive, or else re-partition, completly re-format, then write the files, so all sectors are written.  The longevity of the data is a function of time and temperature.  Disk surfaces and heads can have considerable variation.  Most of the sectors will be OK for years, but some will be marginal.  Most modern drives contain software to report drive 'health'.  There are free programs to read out this information.

If the drive works to the extent of a less-than-3% warranty return rate, the manufacturer ships it.  Some companies have done a lot worse.   SCSI drives cost more, but are built with better bearings, motors, etc. designed for a longer MTBF (Mean Time Between Failure).  Some IDE drives can be had with this higher quality.

Drives are now available with a 'calculated' MTBF of  500,000 hours (about 60 years).  This means that if you have 60 drives running, one will be expected to fail each year.  It does *not* mean any single drive could run for 60 years!  All drives have a design lifetime.  Even sitting on the shelf, the bearing seals will go bad, the surface lubricants will dry out and the connectors/wire contacts will oxidize.  You cannot count on the 'better' drives for more than 5 to 7 years.

The earth's magnetic field is too weak to have any effect on the data.  The coercivity of the magnetic coating is too high.  The residual magnetic fields from the computer's cold-rolled sheet-metal frame and from the drive's pancake-motor drive coils is many times higher at the location of the platters, and they will not have much effect either.

If your drive does not work after being stored in a working condition, do not mess with it.  Take it to an expert.  You can recover some drives with just a light tapping or surface-spinning (frees the heads), or a freezer-bag cold-soak (dry air, no condensation) then a recovery startup.  Sometimes only the controller electronics are bad.  But if the data is critical, you send the drive (plus a few thousand dollars) to a drive-recovery company.

   Regards,
    Ron Fial
_________________________
At 12:32 PM 10/1/2004 -0700, you wrote:
>Hi All,
>
>I have three Maxtor drives on my current system, two of which I use for
>redundant backup of my .wav files.  I called their tech support and ...