Best CD or DVD Recordable Media for Longevity? 81
icepick72 asks: "I have recently purchased a collection of music (on CDs) for a music group that had their final tour last month. Without getting into copyright issues (I'm writing from Canada -- not that it necessarily makes a difference) I would like to know if any CD-R media on the market supports longevity. In the past Slashdot has discussed the degradation of CD/DVD media. How do I go about knowing what the good media is nowadays, and how to get a decent price on it? One company uses this foil or that foil while another uses polywatchmacallit. Looking for good suggestions, and an archived discussion on Slashdot for future reference."
External hard drives (Score:5, Informative)
When USB begins to be phased out for something faster, simply buy whatever the newest hard drive and interface flavor-of-the-month is, and copy from the old HD to the new.
If you are really paranoid, you can just get two drives, and keep them in separate places (preferably separated by 1000 miles or more).
And if you add to that CD-R backups, then you should be prepared for anything.
Re:External hard drives (Score:2)
You should be doing this already anyway, for your photographs and other valuables, so it doesn't take any extra effort.
Re:External hard drives (Score:2)
In other words, using hard drives as long-term backups is a stupid idea.
Re:External hard drives (Score:2)
So tell me, how long does "permanent" DVD-R Media last? No-one can tell for sure. All the dyes age with time, you get reflectivity issues, etc.
And as the GP said, as your need for backup storage increases over the years, you keep buying newer drives of larger capacity, relegating the old ones to the scrap heap (or just kept as old snapshots). So you only keep
Re:External hard drives (Score:2)
A good low-cost drive that supports dvd-ram (along with all the other formats) is the LG-GSA4167 (around $50 or so). However the media will set you back a bit more.
Re:External hard drives (Score:2)
They suck (Score:2, Insightful)
Re:They suck (Score:4, Insightful)
Re:They suck (Score:1)
Re:They suck (Score:2)
Re:They suck (Score:1)
Re:They suck (Score:2)
I have 9 year old CD's that still work without issues, my old win95 email archives test ok.
Copy them every few years to new media, save originals, problem solved.
Re:They suck (Score:1)
Getting on-topic for a change, I have personally found the most reliable media for off-line storage to be the TDK 700MB CD-R. I have occasionally had problems with Kodak and Imation media, and I avoid the no-name brands completely. I also use the TDK DVD+R media, b
Re:They suck (Score:2)
Are you upset that your car isn't like the day you drove it off the lot a few years later? Or ask a person living by a body of water what it does to their furniture and pianos. Are those defective products? DVD-Rs are cheap but have a limited life
Once upon a time (Score:3, Informative)
Any how the biggest killers are UV, heat and moisture. Stop those 3 and you should be making the most of any brand. Mabey inside a p [pelican.com]
Re:They suck (Score:2)
It's tough to say. (Score:4, Insightful)
For some anecdotal info (and links to even more anecdotal info), check out the section 7 of the CD-Recordable FAQ
http://www.cdrfaq.org/ [cdrfaq.org]
To add one more statistically questionable story to the pile, I know several recording studio techs who swear by Mitsui. They're a little more expensive than generics, but you can buy 50 or 100 disc pack from the company itself (or an official distributor) and be reasonably sure of what you're getting. I've had only good experiences with them myself.
But then I've had very few bad experiences so far with any media, and all of those have involved generics with gummy printable labels applied to them, and all were given to me by other people. (My own paranoid technique is to label disks only with a non-alcohol based felt tipped pen.)
On the other hand, if you're goal is archiving the irreplaceable (rather than just stuff that will be expensive to replace), it's hard to beat a pair of hard drives which contain flac (or, if disk space is cheaper than processor time wav) files and checksums for every file. Every year or two you plug in each drive and make sure all the files are good, and when it starts to become hard to find systems that will interface with your old drives, you transfer everything to new ones. When you can pick up a 200 gig ata drive and a USB hard drive enclosure for well under a hundred bucks, it's hard to argue against that sort of strategy. You could do the same with DVDs or even CDs, of course, but checking them becomes a manual hassle.
In any event, make two copies of everything so that if one goes bad, you are likely to have a backup. Keeping one somewhere other than your house doesn't hurt either.
Re:It's tough to say. (Score:2)
Re:It's tough to say. (Score:2)
Re:It's tough to say. (Score:1)
Commercial DVD (Score:2)
I dunno what the other guy was complaining about when he said he couldn't read it straight after he burnt it. Here's a hint: Maybe it's not the disc? Maybe it's your burner. I've got DVD's lying around the place from years ago that I've burnt at 2x and they still work.
Anyway,
Serious: Commercial DVD
Not so serious: DVD-R
Half assed solution: Put the f
Re:Commercial DVD (Score:1)
Try this: (Score:2, Interesting)
Re:Try this: (Score:1)
Re:Try this: (Score:1)
And in any case isn't there a limit to 2G per gmail account?
So it's useless for larger amounts of data, no?
Mitsui MAM-A Gold DVD-R (Score:1)
I bought them at this Canadian retailer...
http://ncix.com/products/index.php?sku=16000 [ncix.com]
old vs. new (Score:1)
Redundancy (Score:2)
Re:Redundancy (Score:2)
Preferably with source code if you can find it, that way you'll be able to compile it in years to come.
Create a hash with a common hashing algorithm, when computers become exponentially faster (Think Quantum Computing)you might be able to extrapolate the data back (Should not be impossible with some additional data such as filename, size, and a brief excerpt).
You could store ALL the hashes on a single disk.
There hasn't been a storage gene
Re:Redundancy (Score:2)
Re:Redundancy (Score:2)
>There are an infinite
>number of files that
>have the same hash. The
>tricky part is finding them.
But if we limit ourselves to files of a specific size, then we get away with a finite (but unpleasantly large) number of files.
In that case, all we have to do is design a quantum computer able to pick the one that is best described by the liner notes.
Granted, it's a bit harder than just buying some extra media in the first place, but certainly a lot more fun.
Re:Redundancy (Score:2)
Assuming a cryptographically perfect 4kbit hash and a 16mbit file, we have 2^(2^24 - 2^12) files (2^16,773,120 files) that match that hash. If the hash isn't cryptographically perfect, this number is the average number of collisions. Note that the files may only differ by a bit or two.
Re:Redundancy (Score:3, Informative)
So say you have a file and running it through par2 with 50% redundancy gives you 100 blocks. All you need at a later date is 50 (any 50) of those blocks and you can recreate the file.
Re:Redundancy (Score:1)
I also have a backup linux box that use to mirror all of my data.
I also have a fireproof safe that I put backup hard drives in. I store the hard drives in army ammo cans, as they are the only truly air
ZipLock Freezer bags, Quart size (Score:4, Interesting)
Freezer bags have extra thick plastic, which provides good, slippery, mechanical protection, too.
If you expect to store the DVDs and CDs for a long time, put the Quart size bags inside Gallon size Freezer bags.
For extreme protection, go to a shoe store and ask them for those little packets of dessicant (moisture remover) that are in each box of shoes. They'll give them to you free. Put one in each Gallon bag. I don't put them in the inner bag because the impurities in the dessicant granules might be abrasive.
Re:ZipLock Freezer bags, Quart size (Score:2)
The chemicals seem okay to be next to DVDs and CDs (Score:2)
Re:The chemicals seem okay to be next to DVDs and (Score:2)
Re:The chemicals seem okay to be next to DVDs and (Score:2)
Chemicals in ZipLock bags are food grade. (Score:2)
However the chemicals in ZipLock bags are acceptable to be next to our food. I doubt they will be a problem for DVDs and CDs.
Re:Chemicals in ZipLock bags are food grade. (Score:2)
Vinegar is acceptable as a food substance. Keeping your dvd or cd media in contact with vinegar would probably end up oxiding the metal layer over time and making it useless.
Re:ZipLock Freezer bags, Quart size (Score:2)
Must be the worst quality commercial CDs ever pressed. Two copies have gone bad with no use (crappy shiny foil labels).
Now they're in slimcases in a vacuum sealed "food saver". Hopefully this works, since the game is getting @#$! expensive to rebuy now.
Verbatim (Score:2, Informative)
Lifetime warranties mean nothing (Score:1)
Re:Lifetime warranties mean nothing (Score:1)
Re:Lifetime warranties mean nothing (Score:1)
I've taken to running dvdisaster on my RW discs before I erase and reuse them to see if they're still reading well. It doesn't have error statistics, but if the read speed drops a lot in an area of the disc, it probably means it's having trouble reading that part of the disc--just don't run dvdisaster while your system is
Re:Verbatim (Score:2)
original stamped CDs are best (Score:2)
Parity (.par) files for extra safety. (Score:4, Interesting)
Plus, I feel that
Although, to be perfectly honest, I just don't rely on CDR or DVDR. I keep a copy of all stuff on a hard drive too. DVD's go offsite, HD stays at home.
Re:Parity (.par) files for extra safety. (Score:2)
Re: Parity (.par) files for extra safety. (Score:2)
I really like Parchive2 [sourceforge.net]. I do wonder if dvdisaster is faster & allows finer-grained recovery, though.
Re: (Score:2)
Re:Parity (.par) files for extra safety. (Score:2)
Why is the liklihood any higher than with
Seems to me,
Re:Parity (.par) files for extra safety. (Score:2)
Regarding ECC, it's true that disks have a lot of error correction already, about 30% of a CD IIRC. However, I've still seen more than my fair share of partially unreadable CDs. I don't know the detail
"Archival Gold" media can be found. (Score:3, Informative)
Personally, I prefer magneto-optical for the important stuff. Disappearance of the SCSI interface will make the drives unusable long before the media degrades.
Silver Gold (Score:2)
Re:Silver Gold (Score:1)
Re:Silver Gold (Score:2)
Was probably on dvdrhelp or something, can't remember thought. Back in the days I also expected gold to be better than silver. Read this only a few weeks ago.
Long way around... (Score:2)
Not everyone has a robotic library backing up their workstation - but even a gen or two older desktop drives are obtainable. Media isn't the cheapest, nor is it great for easy access - but when your CD-Rs fail, and the hard drive you had saved the original AIFF files fails... the LTO tapes are still there.
Etree (Score:2)
FWIW, I've (ab)used a variety of CD-Rs in my car CD player, subjected to extremes of heat and cold, and found that both the Imations and the TY Fujis have held up well. Scratches have caused me more trouble than environmental conditions.
Re:Etree (Score:1)
Correction about Fuji and Taiyo Yuden (Score:1)
Use Metal, not organic-dye, IOW, use DVD/CD-RW (Score:4, Interesting)
Use RE-Writables, not WORM.
RW discs:
*blanking aneals metal-layer in disc
*burning quick-melts spots of metal in disc, so they freeze quickly to different crystallization than the annealed "normal"
*reading means reading the changes in reflectivity that occur ( or differences in polarization, in magneto-optical, IIRC ) in the METAL reflecting the laser-beam.
Write Once discs:
*new disc is "blank"
*laser "burns" organic-dye in writing,
*reading-laser "sees" the diff between burnt and non-burnt as less-transparent vs more-transparent, and the reflective-layer behind-it means that this is usable binary encoding. . . ( beam goes through organic-dye twice and then is read, or perhaps gets-eaten by the burnt dye and then its absence is read. . . )
*organic-dye decays
IF you care about archival, you then store complete versions of your files,
with checksums and ECC on RW discs.
IF you are using organic-dye write-once discs, then you are basing your ability-to-recover your stuff based on Estimates & Marketing Claims(tm). ..
Cheerses
Re:Use Metal, not organic-dye, IOW, use DVD/CD-RW (Score:2)
Comment removed (Score:5, Informative)
Raid and ZFS (Score:2)
Only problem is if the whole system dies (that is if it's always connected and something like the lightning struck or the place burns down and so on), I guess you could send everything over to another machine somewhere else to.
So two separated Solaris machines with atleast 2 harddrives and zfs will d
Re:Raid and ZFS (Score:2)
My archiving system (Score:4, Informative)
I only use Taiyo Yuden DVD-Rs, with a Pioneer 108 DVD-RW drive. Taiyo Yuden invented the original CD-R, and are the only company that still makes discs in Japan. Their discs have excellent quality dye, and provide good quality burns.
When determining how to burn discs, some experimentation is needed. Try different speeds. I have found that a 12x burn gives better quality (i.e. fewer errors, no burn is perfect) than 8x on Taiyo Yuden 8x discs with my burner, but other drives may be different. Try using tools like Nero CD-DVD Speed and DVDInfo to check the number of errors, and that your drive can read the discs at maximum speed all the way to the end. Take a look at the CD Freaks forums, particularly the media tests sub-forum for more info: http://club.cdfreaks.com/ [cdfreaks.com]
I always create parity data. Parity data, in the form of
A note about PAR2 files and DVDs. If your DVD becomes unreadable, i.e. you can't see the filesystem, rip it as an ISO image file. Use a tool that can skip errors, like ISOBuster. Then, use the PAR2 files to try and recover data from it. PAR2 is clever enough to find useful data blocks inside the ISO.
Don't use anything silly like multi-session discs, and make sure your PC can keep up with your burner so that you don't need to rely on "just-link" or whatever they call it. Make sure you verify data after burning (Nero can do this automatically).
Store the discs in a cool, dry place. If you are on a budget, metal "flight case" boxes with CD wallet style holders are a good bet if you keep them in a cupboard out of the light. Don't use flexible wallets. If you have the money, there are commercial storage systems designed for very old books which would probably work well.
Also, be sure to check discs every few years. I generally test a sample of my discs once a year. If any of them show signs of degrading, such as no longer being able to read at maximum speed or high error rates, I re-copy them. My oldest Taiyo Yuden discs are now four and a half years old, and only one (which I may have mishandled) has started to fail so far.
If you are really paranoid, you could keep the parity data on magnetic tape or hard disc. The advantage of only keeping parity data on these more expensive mediums is that it's usually only 5-10% the size of the actual data, which keeps costs down.
I like Verbatim's DataLifePlus Discs (Score:3, Informative)
The discs are also inexpensive. You can pick them up from places like Provantage for under 75 cents each in spindles.
Kodak Gold Ultra CDs (Score:2)
Regards,
Gustavo
dvdisaster (Score:1)
Kodak Gold (Score:2)