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Re: [ARSCLIST] Is recording to Reel-to-reel still the preferred preservation method?
Thanks Ron, for the in depth reply. One of the things I forgot to
mention in my last email was that the tech at Maxtor suggested I ask
these questions of someone who does data recovery, and you, obviously,
turn out to be one of those persons.
Ron Fial wrote:
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've mentioned this in earlier emails, but we back up our files onto
three sets of Mitsui CD's; we don't just use hard drives, either,
although, as I'm working and saving the .wav files prior to making the
CD's, they are duplicated to the two Maxtor hard drives I have on my
system for that purpose. I think I failed to mention that redundancy is
one of rules for our archive.
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 coa tingtodecreasethechancesofthemotorfreezingonstartupduetohead-to-surfacesticking-friction.Ifadrivehasbeenunusedforsometime,besuretobringituptoroomtemperatureforahourorsobeforestartingitup,orevenforadayorsoifthedrivewasstoredatacoldtemperature.Runitfor10minutesbeforeusing,preferablyanhourafteritsoperatingtemperaturestabilizes.Thedrivewillself-calibrateduringthisperiod.
The Maxtor tech said that my particular drives which are ATA/133's with
a separate PCI Maxtor drive card, have the latest design fluid dynamic
bearings which should improve their lifetimes and be less prone to
freezing. But now that you've brought up this inactivity as a potential
problem, we'll change our check times to a couple of months, or even
just keep them powered up. If they are running, but not being accessed,
would that be best for longevity?
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.
That is easily done. We'll reformat every six months per your
recommendation. We use Partition Magic as one of our hard drive
utilities as well Norton's System Doctor & Speed Disk to constantly
defrag. My computer's (Compaq) BIOS has an automatic drive checking on
booting and immediately flags a drive about to fail if Norton hasn't
already found bad sectors in its defragging and System Doctor scans.
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.
Maxtor claims less-than-1% for my drives.
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.
I believe that my Maxtors have: 800,000 hours mean time between failure
(MTBF) in the field.
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.
Yeah, I thought that was a very dubious argument
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.
I'll call you first.
One additional question; you didn't respond to this last part of my email:
Brian gave me a telephone number of one of Maxtor's companies that
specializes in archival tape systems, Quantum, and they say their tape
drives removable data has a life expectancy of 30 years.
This format is specifically for archival purposes.
Also, if tape is more magnetically durable, mightn't Quantum's (or
other vendors) 300 GB cartridges and drives be an excellent solution
for long term storage?
This would seem to me a cross between the virtues of linear tape and
digital storage mediums.
I'd like a response from anyone on this idea.
Thanks a lot,
Rod Stephens
Family Theater Productions
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 ...