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I am in need of backing up some photos from all the phones in the family to a safe location.

I am considering buying just a normal HDD, but I think that an SSD is also an option here?

I know that SSD's don't have any moving parts and can survive any falls while HDD's tend to be very sensetive to shocks etc..

I tried to lookup some information on what is safer to use for a backup: HDD or SSD?

But all the information found is old (2011/2012) and most of them talk only about data-recovery from a failed drive, not actual backup purposes. SSD's have advanced pretty much in meantime so I think this is a question worth re-asking on the internet:

Is it safer to use an SSD for backup purposes or use an HDD instead?

i.e.:

I have to admit that the idea of an SSD surviving a rough "ride" is very convincing but I have heard SSD's last only 5 years whilst HDD's last much longer (10+ years before the data starts to degrade)?

Non-opinion update:

Question: What is the difference between HDD and SSD data retention rates when the drive sits unused/unread for 5, 10, 20, 50 years? Does the charge "evaporate" leaving the data unreadable?

Question can now be answered without opinions.

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    1) A SSD contains zero moving parts 2) A SSD can only survive a fall it was designed to survive 3) define the word "safer" in the context of data. 4) The data on a mechanical drive will last longer then the mechanical parts itself in most cases
    – Ramhound
    Aug 12, 2014 at 18:09
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    @Jason - I am not sure I agree. Of course a single backup does nobody any good since thats a single point of failure.
    – Ramhound
    Aug 12, 2014 at 18:24
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    @Ramhound By definition, any backup isn't a single point of failure. If something goes wrong you have two points: the original, and the backup. If you're talking about archiving/external storage, that's an entirely different subject.
    – Jason
    Aug 12, 2014 at 18:31
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    @Keltari Not DVDs, M-Discs. :) Aug 12, 2014 at 19:00
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    For backup purposes, the issue isn't how long the device lasts in use, it's how long the data on it is readable when the device is not in use. Data on a hard drive lasts longer than data on an unpowered SSD.
    – fixer1234
    Dec 20, 2019 at 22:18

3 Answers 3

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Yes, SSDs are safe to use for backup purposes. (Although, I can't imagine why you would want to, but that's a different subject.)

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A few lessons we should learn from this:

  1. SSDs are not less reliable than HDDs
  2. Modern SSDs are still unproven technology
  3. Multi-layer cell memory is more reliable (but costs more)
  4. Most importantly, any kind of drive can fail. If the data matters, plan accordingly.
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    I like this answer, but one should also note that 1) Without a power source, SSDs lose data much faster than magentic storage 2) Data lost on an SSD is often less recoverable than on HDDs [this one goes both ways, because HDDs have more opportunities to corrupt data in the first place due to head slaps, debris, etc.] Aug 12, 2014 at 21:32
  • @TaylerJones If my backup or archiving drive is an external SSD linked up to the computer, so it will have a power source every time I boot up my PC, is the "Without a power source, SSDs lose data much faster than magentic storage" a concern? Nov 11, 2016 at 20:06
  • @Jason "Although, I can't imagine why you would want to, but that's a different subject" - I was under the impression that SSDs are more reliable, especially because HDDs having moving parts that can break when moving them around. Is my impression exaggerated? Nov 11, 2016 at 20:07
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    @Abdul not necessarily, but a real backup should be off premise anyway. If that is your only backup and god forbid there was a fire at your workstation, all your data is toast. Dec 8, 2016 at 19:44
  • "Without a power source, SSDs lose data much faster than magnetic storage" True but it usually takes at least 1-2 years before there is any risk of this. So if you are using these for incremental backups of a live system where you have a few SSD's that you rotate out on a regular basis than its a non issue but for archival of data that needs to be kept for years than you want to use a different type of media. Also keep in mind that as long as you are validating the backup on a schedule the act of plugging it in to run the validation will allow it to refresh the data. Sep 24, 2021 at 10:33
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When you say backing up family photos, I'm guessing you want long-term, archival-quality storage. If not then you can skip reading this, but if that's the case, then neither technology is really suitable for that.

Two things to keep in mind about SSDs vs. HDDs for backups...

Firstly, SSDs are far more expensive than hard drives. People pay the price premium because of their speed. Backups waste that advantage so you're spending extra money for half the space and none of the benefit. Yes, they're more robust than hard drives, but DVD-Rs and tapes are even more so.

Secondly, hard drives usually give plenty of warning before they die and the data is usually recoverable when it happens. But when SSDs fail, they go from zero to dead quite quickly. One day they work, and the next day they don't -- sometimes for no reason at all. They also have a tendency to eat your data like some kind of bit-monster that feeds on zeroes and ones when they die.

I work in a large environment with SSDs everywhere. In my experience, they're not any more or less reliable than hard drives are. The only difference is that usually there's no getting the data back from a dead SSD.

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  • "Yes, they're more robust than hard drives" Can you explain that a little further please? Also, the reason I was looking to use a SSD over HDD for backup was because I was under the impression that SSDs are more reliable, especially because HDDs having moving parts that can break when moving them around. Is my impression exaggerated? Nov 11, 2016 at 19:58
  • HDDs actually don't often give SMART warnings when they're about to fail. See for example this study by Google: Pinheiro et al., 2007, "Failure Trends in a Large Disk Drive Population" (static.googleusercontent.com/media/research.google.com/en//…)
    – Ralph
    Mar 1, 2022 at 22:24
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It is safe. Tell the people who tell you otherwise they got no clue. A typical customer grade SSD lasts now around 35 years, if you write 20 Gbyte/day on it.

Just take a look at this SSD endurance test to get the hard facts:

http://techreport.com/review/26058/the-ssd-endurance-experiment-data-retention-after-600tb

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  • There are two different issues: one is the number of write cycles until the SSD dies, which you explained is quite large for everyday use. But a bigger problem is that SSD NAND needs to be "recharged" every once in a while; an unpowered SSD is generally only guaranteed to retain data for about a year (or as little as one week in certain situations, for enterprise SSDs).
    – vgru
    Sep 10, 2021 at 8:01
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    @Groo: not really. A JEDEC presentation was the source if these unwarranted, or at least not-nuanced, claims that have been around the internet for years. Check this site: anandtech.com/show/9248/the-truth-about-ssd-data-retention. It mostly boils down to that the tested disks this way were at their edge w.r.t. the number of write cycles they can take, a limit you normally would never reach. (The experiment was set up with a month or so of continuous writing I believe, see the slides here: jedec.org/sites/default/files/…)
    – Ralph
    Feb 18, 2022 at 12:09
  • @Ralph thanks, I was aware of that article, but can you point out where it says that the disks were at the end of their write cycles? I'd like to get the correct information if possible :)
    – vgru
    Feb 21, 2022 at 11:13
  • I see that the link I gave to the slides is broken off. Here it is again: jedec.org/sites/default/files/…. Now, on slide 27 you see the tables that were quoted everywhere at the time. The study these data are based on is apparently done by Intel. I believe slide 34 shows the method they used (runs the SSD to 100% of P/E cycles). However, this was a presentation obviously so we don't know exactly what else has been explained.
    – Ralph
    Mar 1, 2022 at 21:37
  • In any case, I believe, to clarify what I wrote before last comment, they first exhaust the drives in a few days/hours (depending on their capacity/speed) to their maximum P/E cycles. They do this writing in environments with different temperatures, as per the table "active temperature". Then they take offline the drives setup like that and leave them again in different temperatures environments, as per the table "power off temperature", then check data retention.
    – Ralph
    Mar 1, 2022 at 21:42

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