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Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

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191–200 of 204 posts

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#191
I remember when CD-Rs were the savior of all our storage problems, and I weighed in heavily. They were easy to burn and very durable. BUT, just like VCR tapes were doomed because of the ease of coping video, CD's were doomed because of music and video coping. All media types are at the mercy of corporations with their own agendas. Just look a DVDs, Blu-Ray, they told us, would be better and longer lasting as far as use goes. But, really, who buys BR movies anymore?

I love and use all USB drive devises now, and SSD and HDD. But how long before the corps determine it's no longer good for them?

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#192

Totally anecdotal but just a month ago I opened a box from my last moving (ended 4 years ago...) and I found a CD-RW labeled "Backup 2001", which survived 5-6 relocations, even an international one. Well, I put it into an USB DVD player I have aaaand, it starts spinning and spinning and spinning, and nothing shows up in Nautilus. Looking at dmesg I see a few I/O errors on the device. Then, I try ddrescue [1], start e…

Outlook may have used Windows structured storage back then -- but then again it could just be my imagination.

https://learn.microsoft.com/en-us/windows/win32/stg/structur...

e.g. https://www.mitec.cz/ssv.html

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#193
post #170

Earlier quoted context omitted.

>They literally engrave data into a polycarbonate with high melting point instead of writing to a dye. Are you sure you're not talking about pressed (ie. mass produced) discs? I find it unlikely that a blu-ray/dvd burner equipped with only a laser can "engrave data into a polycarbonate with high melting point".

> Verbatim M DISC™ optical media is the new standard for digital archival storage. Unlike traditional optical media, which utilize dyes that can break down over time, data stored on an M DISC is engraved on a patented inorganic write layer – it will not fade or deteriorate. This unique engraving process renders these archival grade discs practically impervious to environmental exposure, including light, temperature a…

One wonders why M-DISC is not included in the original article at all.

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#195
post #103

Earlier quoted context omitted.

Just my photo library is over 1.5 TiB, there just not way to have long-term offline backups of that, you have no choice but to run and maintain a file server and cloud backups

1.5 TiB is not much really. Any mobile HDD will do. I've a whole bunch of them. Oldest were over a decade, no issues at all. The only issue is that they have to be labeled clearly, or you are going to have a hard time to find whereabouts.

I've had really bad luck with the reliability of mobile HDDs in storage. Try to use them after 3-4 years and they just die. Maybe I've just been unlucky?

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#196

Earlier quoted context omitted.

Wondering if you do any checking for bitrot? I mean, if some files on one of your disks became corrupt over time how would you know before it becomes too late to recover it from older backups?

I'm no sysadmin so my knowledge in the field is limited. I'm relying on ZFS mirrors which hopefully should be a bit better than the alternatives at bit rot protection, but admittedly if I was hit by corruption at that level that would catch me unprepared. I'm open to suggestions however.

> I'm no sysadmin so my knowledge in the field is limited.

Same here, but my primary backup is also using ZFS mirrors. I have one cronjob that once a month runs 'zpool scrub mypool' to validate all checksums as a bitrot test, and then a day later another one to email me the results of 'zpool status'. If that email contains "state: ONLINE" then no issues were found.

But I've pieced this together myself and would also be open to anyone's suggestions!

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#197

Earlier quoted context omitted.

Mitch Hedberg sounds right but I remember the joke as being about someone handing out paper advertisements on the street. The doughnut joke is a different one I think. https://www.youtube.com/watch?v=bo5pjBmNyrE Also, for someone who died going on 2 decades ago, he's really got some staying power; I see kids discovering him and liking him to this day.

He made great jokes exclusively in a format that is usually reserved for bad jokes. He was a genius.

So much so it creeps into real life for me from time to time.

About 10 years ago working in the Comerica building in downtown Dallas (you can see it in the skyline photos) I parked in a garage connected by hallways and tunnels to stay out of the heat or rain. There were two sets of escalators in this route. One set broke. Management put up a sign on a stand stating “Escalator out of service” and within about a week somebody opened Word or PowerPoint set it to landscape, printed out “Escalator temporarily stairs, sorry for the convenience” on a piece of paper and taped it over their sign.

I’m sure I snapped a picture of it for the week or so it was left up.

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#198

Totally anecdotal but just a month ago I opened a box from my last moving (ended 4 years ago...) and I found a CD-RW labeled "Backup 2001", which survived 5-6 relocations, even an international one. Well, I put it into an USB DVD player I have aaaand, it starts spinning and spinning and spinning, and nothing shows up in Nautilus. Looking at dmesg I see a few I/O errors on the device. Then, I try ddrescue [1], start e…

Is there a good Windows option for DVD-R and RW recovery?

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#199
post #96
post #63

Earlier quoted context omitted.

But keeping a box of storage media in your closet doesn't cost you anything extra, as opposed to cloud storage.

How expensive is your housing per square foot? I suspect cloud storage is cheaper.

We use square meters in Denmark. The diameter of a CD/DVD is 120 mm, so you can fit 64 CD's per m² if you order them in a grid (more if you do not) A CD is 1.2 mm think. The ceiling height in my apartment is ca 2.7m, so I could fit 14400 CD's per m². If a DVD can store 10 GByte, that is ca 144 TByte.

The average rent per square meter is about $20/month (more in Copenhagen, less outside the big cities).

I suspect I can not store 144TByte in the cloud for $20/month.

You might argue that I do have that many DVD's. But then I do have many small corners and shelves that is not much use for anything else. And it would be even more unlikely to be able to store say 14 TByte in the cloud for $2/month.

Re: Longevity of Recordable CDs, DVDs and Blu-Rays (2020)

#200
post #96

Earlier quoted context omitted.

How expensive is your housing per square foot? I suspect cloud storage is cheaper.

We use square meters in Denmark. The diameter of a CD/DVD is 120 mm, so you can fit 64 CD's per m² if you order them in a grid (more if you do not) A CD is 1.2 mm think. The ceiling height in my apartment is ca 2.7m, so I could fit 14400 CD's per m². If a DVD can store 10 GByte, that is ca 144 TByte. The average rent per square meter is about $20/month (more in Copenhagen, less outside the big cities). I suspect I ca…

Thanks for doing the math; you're right!

Google Archive storage is $0.0012/month (3x cheaper than Amazon Glacier, which surprised me). 144TB would be $173/month, so 9x cheaper to keep in your home.

I think your estimate of how many DVDs you can put in a given space is a bit optimistic: you're assuming no protection between discs and that a floor-to-ceiling tower is stable. If instead we imagine putting them in cases that double their thickness and putting collections of them in boxes that add 10% to the total height, though, it's 4x cheaper to keep them in your apartment. But if you use Blu-ray instead of DVD it's 20x cheaper!

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