While i've had generally solid experience with sandisk for almost 20 years and had a few old drives (which i hear are slc-based so its not surprising) hold files for over 5 years no issue, i recently almost lost over 4 years of photos.
I had purchased some lexar drives from costco since they were dual interface (usb A / usb C) about 2 years ago, and it was usefull to just get some pictures off my phone. I usually don't rely on such a setup for long term but as with all things I was delayed tending to it. I figured there were 2 per box so i just copied them twice, and diffed them several times to make sure they were exact copies.
After 24 months, one of the drives had a %95 loss, almost every picture was lost cut-off bottom half or so. The other drive surprisingly seemed fine, though it had been plugged in every 6-9 months I recall, as I wanted to browse it a few times, it seems that this action saved the volume. Upon further inspection the good drive still lost 10 pictures in about 5 thousand, so it wasn't perfect.
Lexar.
https://www.ebay.com/itm/176810492981?chn=ps&_trkparms=ispr%...
If these are JPEGs with a grey or green lower half, it's likely only a few 16x16 macroblocks are corrupted and you can recover the rest.
This cannot be done programmatically because you have to guess what the average colour of the block was, but it can be worth it for precious pictures.
https://www.tomshardware.com/pc-components/ssds/fake-samsung...
I remember years ago working on the Wii, and there was a restriction on how often you could read the flash to avoid premature wearing. Not sure if that was just the specific type of storage, as googling suggests that NAND is subject to this and NOR isn't. I think pretty much all USB drives now use NOR flash, so maybe this isn't actually an issue any more.
DRAM works that way but flash doesn't. Read disturb is a different issue.
pretty much all USB drives now use NOR flash
Nope, NOR flash is much more expensive than NAND so NOR is only used for firmware and everything else is NAND.
This only happens very rarely, though more frequently as NAND flash goes QLC and beyond.
Besides, other experiments have shown that data remanence is way more of an issue with drives that are almost completely worn out (way beyond their specified TBW) and about to croak. Even then you only get rare bitrot that can be checked for and compensated quite cheaply in most cases.
If you take fresh media, write it just once or a few times at most, use substantial overprovisioning to keep the drive in its fast pseudo-SLC mode, and reread the media periodically, NAND can be a good enough storage system for most casual needs.
For the rest of us, a USB spinning rust hard drive formatted as exFAT is going to be hard to beat. You'll be able to plug this into virtually any computer made in the next few decades (modulo a USB adapter or two) and just read it. They are cheap (even allowing for the rising cost of storage), fast, and most importantly, they are easy. The data is stored magnetically, so is not susceptible to degradation just from sitting like SSDs or flash drives are.
Of course, you should not store any important data on only ONE drive. The 3-2-1 backup rule applies to archives as well: 3 copies, 2 different media, 1 off-site.
If we’re talking the average tech-illiterate to literate-but-cost-and-space-constrained person, probably Blu-Ray. A burner+reader combo with a stack of dual-layer discs is probably cost-effective. High-capacity HDDs would probably be equally effective if you can guarantee that they’re stored away from accidents and mishandling, but if it requires a SATA-to-USB adapter with assembly then it might possibly be out of reach for some consumers, and any risk of damage from movement could rule it out entirely.
If we’re talking tech-savvy consumers who don’t have the IT budget of a corporation, maybe LTO-5 or LTO-6 tapes could work. Tapes themselves are very affordable and have a good shelf lifespan. Used libraries can be had for under $600. The primary issues would be finding one with an interface that works with your existing equipment and software to support tape read and write.
First the elephant in the room. Why solid state? because the drives to read the media are often the weak link. When the drives are no longer being manufactured how hard is it to make one? reading solid state drives is a relatively low precision electrical process compared to the high precision mechanical process needed for most media.
First on the chopping block was bulk storage. It tends to be delicate and hard to read and short lifespans. But if I limited myself to small storage there are some interesting options. fusible proms were promising but top out at a few megabytes. Mask roms? does anyone offer a mask rom service anymore?
Put a mask rom into a sd card... no, sd cards are too physically small. For a song album we want something bigger to put album art on. A thing the size of the original gameboy cartridge with a usb interface and a mask rom?
My conclusion, for that specific goal, indefinite future storage of a song album. Vinyl records. low tech enough that it is easy to make a player for them.
My guess is: regular graphite pencil on porous paper is best. Any ideas about further things I have to take into account?
Pencil definitely lasts if the paper is undisturbed. I have some paperwork that's 100+ years old and with legible pencil text. On the flip side, if the paper is handled a lot, the writing will gradually fade because graphite particles just sit on the surface and can flake off.
On some level, the medium is your main problem. Low-grade paper, especially if stored in suboptimal conditions (hot attic, moist crawlspace, etc), may start falling apart in 20 years or less. Thick, acid-free stock stored under controlled conditions can survive hundreds of years.
Acid-free paper sounds like the way to go. Do you have experience with this? Or is it common knowledge? Just curious!
I also read letters from my grandparents, stored by my parents in a simple shoe box. No special conditions, just light-free and inside the home for decades. They were still very much readable. I did not pay enough attention, but I guess it was blue ink from back in the day that they used.
Do you just use regular graphite pencils, like with the HB scale or something?
The engraving pen on glass is a good one. Any experience with it?
All I can say for sure is that you should not trust any flash for long term storage, thumb drive or otherwise. In serious enough, high usage, high heat enviornments where everything working without problems or delay is part of what they are paying us to be responsible for, it is standard practice to clone fresh images to nvmes every time, with multiple spares that can be swapped out in minutes when they inevitably fail anyways.
"I filled 10 32-GB Kingston flash drives with pseudo-random data."
"The years where I'll first touch a new drive (assuming no errors) are: 1, 2, 3, 4, 6, 8, 11, 15, 20, 27"
And from the blog: "Q: You know you powered the drive by reading it, right? A: Yes, that’s why I wrote 10 drives to begin with. We want to see how something works if left unpowered for 1 year, 2 years, etc."
I suppose your `dd` implementation itself could do so, but I don't know why it would.
I will never forget when I mixed up `if` and `of` during a routine backup.
`cat /dev/sda > /mnt/myDisk2` is so much safer, explicit, and in unix norms. It's also faster because you don't have to tune block size parameters.
Plus you can also do `pv /dev/sda > /mnt/myDisk2` to get transfer speed details.
Friends don't let friends use `dd` where `cat` can do the same job.
I'll probably get a spinner and a flash drive and hope one of them survives the years.