Ask HN: Long term local physical backup media? | Hacker News Reader

Ask HN: Long term local physical backup media?

6 pointsplg14 comments

In the 90s, used to be I burned docs & data to CDr media and put them in my bookshelf at home for long term archive. I can still read these CDs today, 30 yrs later. Success.

What is today's equivalent?

Hard drives make me nervous because they have moving parts. SSDs make me nervous because :shrug:. Tape backup seems like a hassle and expensive. I don't want cloud storage (e.g. amazon glacier or the like) because I don't want ongoing costs.

Are CDr still a thing? Am I being too anxious about HDs or SSDs?

Advice appreciated.

View on HN

CDrs still are a thing, and may work "about as well".

The only surefire way for long term archival storage for the average user is to use multiple methods, and check them from time to time.

It's all a matter of cost vs how much you want to archive. If it's in the "CDr size" you can just make tons of copies, some will probably survive.

But you can also just keep that much around on every device you own and checksum it regularly.

Tape is pretty good, but even there you'd want multiple copies on different media. You could rent a drive or buy a used one, write out your tapes, and then sell the drive again.

Hard drives sitting unpowered have a "decent" change of firing back up after 10+ years, if you have the connector (externals are probably easiest) - but even there I'd want multiple copies from different vendors.

yeah I'm trying to follow the 3-2-1 idea, I have (1) a copy on the internal HD of a mac studio ultra, (2) a copy on a synology NAS ... both (1) and (2) live in the same server room. I'd like an offsite 3rd copy as well.

I had been using Arq with their paid cloud storage option, but the backup has stopped working and after 2 days of polite back and forth with their support they are now ghosting me (!) which is not a _great_ characteristic for someone selling archival cloud backup solutions.

I could of course have the Synology NAS backup/archive to one of several cloud services (AWS, Backblaze, Google, Wasabi, ...) but I would love a physical option.

For size I am dealing with something on the order of 1.5 TB currently, perhaps growing to 3-5 TB over the coming years. So perhaps too large for CDs.

That's peanut-sized, to be honest. I would just get a few large USB hard drives when they're on sale (5TB is like $100 new now) from different brands and cycle them.

If you wanted to go a bit fancier you could get an RDX drive https://www.overlandtandberg.com/products/rdx-removable-stor... and some cartridges, but you're looking at $100-200 for the drive, plus the cartridges are more expensive than USB: https://www.rdxworks.com/Tandberg-Data-RDX-2TB-8789-RDX.aspx (A 5TB cartridge is $560, you could buy five USB drives and make five copies and that would likely be more reliable than one backup cartridge unless you were really unlucky).

They're designed for backup and archival and just appear as a USB drive. I'd go that way for business or if you're cycling cartridges a lot.

And out of your data, you can designate "Very important" things like tax returns, documents, etc (which is probably a small portion of the total) and burn those to CD or DVD as additional security.

In terms of hardware, RDX cartridges are just bog-standard SATA hard drives in proprietary enclosures, so no more or less reliable than SATA hard drives in equivalently rugged USB enclosures.

I'd actually argue that RDX carts are a bit worse than ordinary USB external hard drives in long-term archival applications, due to an unusual design decision: the SATA hard drives internal to RDX cartridges are locked with factory-preset ATA passwords that serve no apparent purpose other than to make them non-interoperable with standard SATA ports and enclosures, which are more common than RDX drives by several orders of magnitude.

You could use M-DISCs, which look like traditional CDs nut are made for long-term storage and should be readable much longer than other CDs, DVDs and Blu-rays. The optical drives for burning M-DISCs are readily available and not very expensive.

If you're only looking to store a small amount of data then writable discs (CD, DVD, etc) are still easily available. Just make sure to keep them out of direct sunlight as that can affect their long-term readability.

If you need to store a larger volume of data then you'll probably be looking at tape of some form of hard disk/SSD.

Either way you can reduce the risk of loss by having a regular process of copying the old data to new media and keeping both the old and new media - that way if one copy of your data fails you'll still have other copies that you can use.

My current thinking.

CD's are the equivalent of CD's. Like you said, thirty years later they still work.

DVD's are probably close.

Spinning disks are probably ok if used as write once.

All of these have lots of compatible hardware and software.

Tape is great at scale. But you're not at scale.

The cloud is one declined credit card away from erasure.

Good luck.

BD-R writable DVDs seem to provide either 25GB (single layer) or 50GB (double layer) storage, and seem like they would have longer lifetime than spinning discs, SSDs, or tape. I guess if I can deal with 50GB chunks that may be the best option.

>80% of my most expensive (at the times) CD/DVD-R/RW disks became unreadable after 7-10 years.

Is there any evidence BD-R are better?

It looks like a RAID setup might remove your concern for moving parts, while benefiting from a cheaper storage price.

I had this concern myself and eventually I gave up and do it on cloud.

m.2 SSD with redundancy treatment e.g. par2, should get the job done and happier to work with, because r/w rate is the highest among all options.

Crystals

Can you provide more details?

Not yet. But there's an opportunity here, somewhere. It's just going to be very hard to implement. Remember the memory crystals in Superman, used by the Kryptonians?

Reply on news.ycombinator.com