Question Is this a tough choice? Blu-rays or external HDDs

[Perene]

Let's say someone wanted to give to you 4 TB for your most important backups. For free. But you only had 2 choices: either a) an external HDD, or b) 150 (more or less) Blu-ray discs, which I assume will have 25 GB each. What would you choose? Don't mind the fact that it's a hassle to handle so many discs; the choice here only matters in terms of preserving the contents, for many years, perhaps your lifetime.

As far as I researched, there is no such thing as a "reliable" HDD, even in the best brands you can easily find reviews saying the drive either was DOA or died a few weeks later. And when that happens, it's costly or impossible to recover everything lost. I mean, from the looks of it, we probably have more chances winning the lottery than any of our internal (and perhaps worse) external drives not dying without further notice. Which is a tragedy, because online backups are anything but cheap and having enough space for datahoarders like myself.

On the other hand, I am curious about these discs, because even if a few fail, it's not all of them at the same time, I guess. So if we analyze this purely objectively, if we are storing 4 TB of data only to make sure this isn't lost, not to access it all the time (because we may have all of this in our SSD/internal drive anyway, it's only when needed that we may get the disc/drive again and copy the contents), what makes more sense?

 

[Tech Junky]

As a cold backup an SSD / tape / optical makes more sense than HDD.

4TB isn't that much considering capacities these days hitting up to 20TB/HDD that you can buy today.

Less moving parts though means longer survival of the medium typically. USB SSD's make sense. I have a USB drive though that acts like an internal SSD when plugged in. SanDisk Extreme Pro 256GB was ~$60 on Amazon. hits ~450MB/s and fits in my pocket. Otherwise NVME enclosures or TB enclosures work as well. Slightly larger format but, also considerably faster and adaptable when you swap the internal drive for something larger or smaller. 8TB drives might run $800 though. 4TB though IIRC are hovering around $200 right now.

FREE though in context of your OP I would go with the HDD for speed but the disc for sitting around for a long period of time. They're both lacking durability but the HDD upside is being able to add/remove data more easily as time goes by. The enclosure will likely die before the drive though as they are temperamental unless you buy something more substantial. The cables tend to be cheap as well when provided with the enclosure and cause issues as well.

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[Shmee]

I would actually recommend a decent HDD for cold storage, probably a WD Gold or similar enterprise drive would be the choice. Good 3.5in drives are pretty reliable, much more so than cheap 2.5in drives. And quality internals are more reliable than externals.

You could connect it to a USB dock when doing backups. Obviously, it is important to keep it safe and disconnect it when not in use. It is also important to have multiple backup methods, not just one.

As for SSDs, a good one can be used for cold storage, but this is not an ideal use, I believe they actually retain data worse than mechanical drives when not powered, though this will also depend on the type of NAND used.

 

[boondocks]

No matter the best medium employed, redundancy is important.
Saying that, I once had HDD's die on two different machines within a week or two of each other.
Both had almost identical files, although I was lax updating/copying to the second pc.
C'est la vie.

 

[Tech Junky]

lax updating/copying

Nice thing about Linux is cron and rsync to automate things on a schedule.

 

[GunsMadeAmericaFree]

I used to have a Qic tape drive in one of my system's bays. I seem to recall that it would back up up to 400 megabytes of data, which at the time was PLENTY to back my entire system up onto one tape. I have to admit, I haven't looked into tape backups since the late 90's. Is there an inexpensive modern variant that one can put in a 5.25" drive bay?

 

[mindless1]

Let's not pretend you are forced to pick between the two, because that would be silly and a waste of time when tape drives exist. If you just want cheap and easy, sure, get an external HDD to make a redundant copy of the data. Redundant meaning you need two of them if this data isn't still live online too, or better still, get the tape drive anyway, store the tape off-site, perhaps in a safety deposit box.

 

[mikeymikec]

@Perene

You will find reviews of any bit of electronics asserting that the product was DOA. There simply aren't any exceptions.

If hard drives were as unreliable as "they mostly fail within warranty", hard drive manufacturers would have gone bankrupt long ago, and I'd be surprised if any electronics business model that had to factor in double-digit percentage failure rates would survive for long. I've been using hard drives for backup (I use internal drives that I plug into a USB 3.0 SATA HDD enclosure) for close to twenty years and zero have failed. However I'm not going to claim anywhere near-perfect reliability for hard drives; in my line of work (computer fix-it company for twenty years) of course I've seen many hard drives die, probably a few hundred.

SSDs would obviously be faster to back up to, but they're also more expensive and there's research suggesting that their ability to store data reliably in the long term while being offline for long periods of time is problematic; it's an issue of bit rot relating to varying temperatures (comparing online to offline). However if I was using an SSD for backups at least every month then this probably wouldn't concern me.

BR discs can go up to 100GB in capacity. However, if my experience in writing a dual-layer DVD (~8GB) was anything to go by, it'll take freaking ages to write. That DVD took about 45 minutes (this was in the last 12 months; I decided to diversify my backup strategy to also include more essential data to be backed up to DVD occasionally). Plus, there's always the chance of writing a dud, as well as a poor choice of media resulting in a backup not lasting very long.

IMO hard drives are your best bet. I have multiple hard drives, each storing a backup set. I have another hard drive dedicated to storing datestamped backup sets of the more essential parts of data I don't want to lose. I keep information about my backups (what was backed up and when) in a spreadsheet.

Any backup strategy should allow for the possibility of backup media failure. IMHO, the likelihood of your main system suffering catastrophic data loss plus two backup sets (assuming you have tested your backups occasionally) being compromised all spotted at the same time are some pretty long odds.

 

[GodisanAtheist]

No matter the best medium employed, redundancy is important.
Saying that, I once had HDD's die on two different machines within a week or two of each other.
Both had almost identical files, although I was lax updating/copying to the second pc.
C'est la vie.

-I cannot stress this enough. You need 3 copies of the data, and they need to be *stored in 3 different places*.

Don't want to have all your family photos and home videos destroyed cause they were stacked in the same place that caught fire.

 

[Perene]

I received a batch of BD-RE (23 GB) this week. 50 units.

To fill one of them, it takes exactly 1 hour and 20 minutes in my old drive (at 2x, and the discs do not allow any other speed). No, it doesn't take 2 minutes less, 1 minute more - exactly 80 minutes (at least the last 12 I burned...), since I always check "verify data after burning" with CDBurnerXP.

The best app to create a catalog is this one, I don't think any other comes close: https://www.wincatalog.com/

It can also check video contents and list their internal tracks, something I wanted but was unable to do with multiple at the same time (using MediaINFO).

Also, for storing I followed the tips mentioned in this link: https://www.digital-scrapbooking-storage.com/best-jewel-case-for-storing-cds-and-dvds.html

A standard CD jewel cases, 10.4mm thick, is what I put ALL discs. I checked the alternatives and they ALL suck. Amaray Keep Cases are good, but waste too much space, so not an option.

 

[Perene]

Perhaps the best input on this subject...

View: https://www.youtube.com/watch?v=qbxaPc2Xf5M

The article he mentions:

https://discussions.apple.com/docs/DOC-6031

And for those in doubt if CDs/DVDs/Blu-rays are the same:

5:30 - "Today, CDs are no longer considered to be reliable as long-term storage media"