I’m old enough that we used floppy and then CD/DVD drives for storage, and then flash drives and external hard drives. But I recently was told those aren’t good long term storage options (ex: family photos or sensitive documents). Why are they poor options for long term storage, and what should be used instead?
In: Technology
Flash drives are great for storing stuff long term, as long as you don’t read/write that flash drive often. Flash memory generally has very good “data retention” characteristics, but lousy “write/erase endurance”. If you are going to use a flash drive for long term storage, take a fairly virgin drive and put the stuff on it you want to save, then put it in a safe place. Just reading the drive isn’t much risk, but adding or changing data is.
But whatever you do, don’t rely on a single storage device for things that you want to be damn sure that you won’t lose. Redundancy is a cure for many ills.
Personally, for critical data I use a RAID 1 system (redundant hard disc drives) and cloud storage. The RAID system runs a check every week and tells me if any data has gone bad. So I’ve got three copies of everything.
All media degrades over time, and some are susceptable to corruption and complete loss from light, moisture, magnets, and time itself. It’s called “bit rot”. Over time everything degrades. When using physical media and storing data on an incredibly tiny area, even a speck of dust or an errant radioactive particle could corrupt data.
Flash storage works like a bunch of light switches. One for each 0 and 1. A super tiny blip of electricity turns it on or off. There are billions of them. So they are fast to read and write, but like real light switches, they have a lifetime of a certain number of flips before they break. Even more so, the static from your finger could fry millions of those switches instantly.
Older disks had the same issue, but they were more like paper scrolls. As long as the scroll itself was okay and didn’t fall apart, and the ink was still readable, the it could be read, but light, magnets, and other things “fade” that magnetic “ink”.
Have 3 copies of your files, 1 copy at a remote location, verify the files once every year or so and don’t worry about it.
I like the [M-Disc](https://en.wikipedia.org/wiki/M-DISC) Blu-Ray media. These don’t use dyes so they don’t fade and you can fit 25 GB on each disc. Actually they have multi-layer discs up to 100 GB but they’re disproportionately expensive and I don’t trust more than one layer on optical media. Yes, this is fiddly and not cheap but I think it’s the safest choice for home archival purposes.
My second choice is just USB external spinning drives. These are cheap enough to buy every year or two and copy your data on to them. Personally I’d stay away from the models using shingled writes and especially helium but that’s getting harder and costs more per byte.
Anything you store your data on is going to degrade over time. Also, it will become obsolete. Even, for example, if your 51/4 floppy was still good now, how would you read it now?
Store your data in two or three places, physically separate, and upgrade that medium, copying over the data to new media, every few years.
Latest Answers