I would never buy a no-name SSD. Did it once long ago and got bit, wrote a program to sequentially write a pseudorandom sequence across the whole volume then read back and verify, and proved all 8 Pacer SSD's I had suffered corruption.
Discussion on the original source: (20 points, 3 days ago, 5 comments) https://news.ycombinator.com/item?id=43702193
Related: SSD as Long Term Storage Testing (132 points, 2023, 101 comments) https://news.ycombinator.com/item?id=35382252
I didn't think it was controversial that SSDs are terrible at long term storage?
This is a known issue. You have to power up your SSDs (and flash cards, which are based on even more flimsy/cost optimized version of the same tech) every now and then for them to keep data. SSDs are not suitable for long term cold storage or archiving. Corollary: don't lose that recovery passphrase you've printed out for your hardware crypto key, the flash memory in it is also not eternal.
Endurance is proportional to programming temperature. In the video, when all four SSDs are installed at once, the composite device temperature ranges over 12º. This should be expected to influence the outcomes.
For long term storage, prefer hard drives (careful about CMR vs SMR)
If you have specific random IO high performance needs, you can either
- get a SLC drive like https://news.solidigm.com/en-WW/230095-introducing-the-solid...
- make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578
Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested: I learned my lesson for M2 2230 drives https://www.reddit.com/r/zfs/comments/17pztue/warning_you_ma... which seems validated by the large numbers of similar experiences like https://github.com/openzfs/zfs/discussions/14793
> (careful about CMR vs SMR)
Given the context of long term storage... why?
Untested hypothesis, but I would expect the wider spacing between tracks in CMR makes it more resilient against random bit flips. I'm not aware of any experiments to prove this and it may be worth doing. If the HD manufacture can convince us that SMR is just as reliable for archival storage it would help them sell those drives since right now lots of people are avoiding SMR due to poor performance and the infamy of the bait-and-switch that happened a few years back.
After I was bamboozled with a SMR drive, always great to just make the callout to those who might be unaware. What a piece of garbage to let vendors upsell higher numbers.
(Yes, I know some applications can be agnostic to SMR, but it should never be used in a general purpose drive).
> - make one yourself by hacking the firmware: https://news.ycombinator.com/item?id=40405578 Be careful when you use something "exotic", and do not trust drives that are too recent to be fully tested
Do you realize the irony of cautioning about buying off the shelf hardware but recommending hacking firmware yourself?
Tape is extremely cheap now. I booted up a couple laptops that have been sitting unpowered for over 7 years and the sata SSD in one of them has missing sectors. It had zero issues when shutdown.
Is tape actually cheap? Tape drives seem quite expensive to me, unless I don't have the right references.
Tapes are cheap, tape drives are expensive. Using tape for backups only starts making economic sense when you have enough data to fill dozens or hundreds of tapes. For smaller data sets, hard drives are cheaper.
If you care about long term storage, make a NAS and run ZFS scrub (or equivalent) every 6 months. That will check for errors and fix them as they come up.
All error correction has a limit. If too many errors build up, it becomes unrecoverable errors. But as long as you reread and fix them within the error correction region, it's fine.
What hardware, though? I want to build a NAS / attached storage array but after accidentally purchasing an SMR drive[0] I’m a little hesitant to even confront the project.
A few tens of TBs. Local, not cloud.
[0] Maybe 7 years ago. I don’t know if anything has changed since, e.g. honest, up-front labeling.
[0*] For those unfamiliar, SMR is Shingled Magnetic Recording. https://en.m.wikipedia.org/wiki/Shingled_magnetic_recording
> run ZFS scrub (or equivalent) every 6 months
zfs in mirror mode offers redundancy at the block level but scrub requires plugging the device
> All error correction has a limit. If too many errors build up, it becomes unrecoverable errors
There are software solutions. You can specify the redundancy you want.
For long term storage, if using a single media that you can't plug and scrub, I recommend par2 (https://en.wikipedia.org/wiki/Parchive?useskin=vector) over NTFS: there are many NTFS file recovery tools, and it shouldn't be too hard to roll your own solution to use the redundancy when a given sector can't be read