Helloooo, For a little while I have been looking into other methods for stable 'cold storage' 'double' backups for some of my data that's sitting across multiple harddrives. I have eventually come to settle on optical media, and more precisely CDs/DVDs because their price point is unmatched. Just gonna blab about the specifics and the thought process here. Present my (jewel) case, if you will...
Sections
What I Wanted
I'm gonna explain out the first sentence of this post a bit more:
- 'stable': a storage medium that likely won't be destroyed if dropped from a height of 15cm+, and won't be damaged by vibration over time (like HDDs).
- 'cold storage': one that doesn't need power or much maintainence to retain it's data. Ideally, to avoid data loss/corruption, SSDs should be powered on/accessed once per year, and HDDs should be totally rewritten about every five years.
- 'double backup': backup of a backup, to compensate for hardware failures. Best to use a medium you can leave alone for a long time (HDDs are still a good option for this, to be fair)
Additionally I wanted some data longevity while also not spending much money which led me to rule out a few options, especially considering the idea of having multiple read/write devices (drives) in case your only one fails.
throwing around a bunch of local currency prices below. when I say $100; -30 for USD, -40 for EUR, -47 for GBP, x3.6 for BReal, x12 for MXPeso ;)
- Linear Tape Open (LTO): A magnetic tape media used for professional and pro-sumer archiving. Huuuugggeee storage capacity and longevity, for a ludicrous price. Invididual tapes new are easily over $100 each, used varies $30-100+, and the drives to read/write them are in the thousands. While it was interesting learning about this stuff, it really is a commercial business product.
- Hard Disk Drives (HDD): Ubiquitous magneto-optical drives, 'ol reliable. These are(/were?) an reasonable price point for storing large quantities of data as a consumer. I mentioned some of it's problems above; I have had one break from a drop of literally 15cm (6 inches?) before and the data recovery quote was $400 (the content on that drive cost $0, lmao), also had one become unusably damaged by vibration in a laptop within six years of purchase, and 'ideeaaallyyy' it is recommended to fully rewrite them every 5 or so years to prevent data loss (however my 2004 Xbox HDD is uncorrupted with longer stints than that). It just adds a lot of considerations to how they are stored and maintained over time. Beyond this, their prices new are currently rising for the benefit of AI slop servers (like SSDs and RAM), and while used prices can be more reasonable they come with reliability concerns.
- Blu-ray Discs (BD): The newest optical media for consumers. Large capacities starting at 20GB, with XL discs hitting 100GB. However, many big drive and disc manufacturers (Sony, Pioneer, + more) have announced the cessation of production over the past few years. The most basic discs are about $5 each, with new drives at about $200-300 (double that for a backup one), and 10 year old used laptop drives still around $90-150. Those prices will likely increase as less drives/discs are made, and the more afforable basic discs have apparently lower longevity than CDs and DVDs (10-20 years vs 20-50+). There are 'long-life' and M-Discs (meant to last a millenium) but they clock in at about $25 each.
Some other things considered along the way;
Flash Storage: SD cards and flash drives vary wildly in quality, with the more reliable being more expensive. They are also an enormous target for counterfeiting; branded packaging and plastic casing can be copied 1:1 and put up for sale on popular sites with little to no oversight. These counterfeit flash drives will often stop working after a few uses or a certain amount of GBs put through them. The only way to truly tell is to rip them open and look at the chips inside, at which point they are destroyed. You are far more likely to get legitimate stuff from brick and mortar shops (assuming no product swap occured in store), as they have the buying power to actually acquire from manufacturers, and they can't just delete their store after scamming you, lmao. But even with them, many large physical stores' online services are flooded with thousands of 'marketplace' items that leverage the 'trust' of the physical store to sell dropshipped junk. I was looking at the cost of printers online at a local discount department store recently, and filtering out 'marketplace' items removed 30,000 results. And to be clear, this isn't like a 'oh these poor major corporations with brick and mortar stores' thing, they are the ones facilitating this and willingly laundering scam products for commission. Flash storage is also effected by a capacity-cost paradox that I will explain in the next point.
Capacity-Cost paradox: If a storage medium is re-writable, with a large capacity, and higher cost-per-gigabyte rate, you are less likely to permanently use this for long term storage. For example; it makes sense to buy a large capacity micro SD card for long term cold storage of your data, but if that little card cost $60 (for 128GB) you probably don't want to leave it anywhere unattended like garage storage. It is also still extremely useful, it can move huge amounts of data relatively quickly, and is a main storage medium for many common devices like smartphones, tablets/2-in-1s, gaming handhelds, it can even plug into your computer (with an inexpensive adapter if no slot is available). Compare this to optical discs, or camcorder tapes of the past, which are literally useless until you write data on them, are comparatively inexpensive (50c or less for a 4.7GB DVD±R, $1-3 for 60 mins tape), with less 'useful' capacities and transfer speeds, that in turn cause much less of a hang up (and fear of unused capacity) around storing them long term. I wrote a bit more about this and how it likely contributes to a post-tape era of data loss in a post on my other site.
Using the tools I have: I look around my home, all I see are DVD/CD burners. Every laptop made in the past 15 years with an optical drive almost certainly has a DVD multi-drive burner (multi referring to the different formats of DVD, more on that later). I have three functional laptop burners, plus an external USB-DVD burner I got with my main PC in 2020 for about $50 (still roughly this price new), and a fifth DVD burner unplugged in my server PC (used HP Prodesk G3 600 SFF that was $80!). I also have a ream of blank inkjet printable DVD+Rs I got when making a present for a friend, and a handful more blank CDs from going through discs at my folks place a while ago. And further on this, burning discs doesn't require the internet, a modern computer, or even a currently supported operating system. Windows and Mac have had disc burning utilities built in for decades, and I've just been using XFBurn on my linux computers cause it's easy and graphical. My 2011 Toshiba Satellite burns just as well as my custom PC from 2020 (+ the external drive).
The signs all point me towards Compact and Digital Versatile Discs...
CD/DVDetails
This medium is fine for my use case, I don't plan to back up terabytes of data for the time being. Regardless of how much I expect to put on discs, it is still going to require some planning in order to sort and categorize stuff to fit within the capacity chunks of the different types of discs (more on that near the end). These discs will mostly be;
- CD-R/RW = 650-870MB: Good for grouping together smaller data like text files, PDFs, emails, scans, etc. Also obviously holds audio very well; roughly 74-99 minutes. Basic discs are around 30-50c each, maybe up to $1-2 for long-life ones (more on longevity later)
- DVD±R/RW = 4.7GB: Good for photos and video. Depending on the format of video, each disc could hold multiple television episodes or 1-2 feature length films. Basic discs are around 50c-$1 each
- DVD±R/RW DL = 8.5GB: Dual Layer single sided discs with almost twice the data capacity, good for video. Basic write once discs (DVD±R DL) are around $1-2 each.
The discs above represent an acceptable price point and availability for me. There are more formats around but they are less popular, more expensive, and some aren't even made anymore. A bit more info on different types and formats below:
- R or ROM: Read Only, can only be written to (burned) once. Good for stuff you likely don't need to touch/edit again like personal photos or documents.
- RW: ReWritable, can be re-written up to 1000 times. Good for a backup you may want to rewrite multiple times, like I have double backed up my websites to a CD-RW.
- DVD+ vs DVD-: These are two formats of DVD made by two different corporate alliances. Minus (-) came first in the late 90s, and plus (+) came around the mid 00s. The difference is absolutely nothing from a consumer point of view (something about 'timing'), this is why I have used the plus minus symbol (±) throughout. Essentially every DVD burner drive made post 2010 is capable of reading and writing both formats and CDs, these are known as 'multi' drives. Inexplicably, one format is sometimes slightly cheaper than the other, so that's what I will grab (it's different nearly every time).
- Dual Sided DL: The highest capacity DVD is Dual Sided with Dual Layers, sitting at 17.08GB (almost a base Blu-Ray). I genuinely couldn't find any double sided dual layer blanks anywhere online after a brief search, which likely means if I ever do they will be expensive. Apparently more error prone too, as the laser goes through layers from the bottom.
- DVD-RAM: A DVD that can be written to and randomly accessed like a harddrive, with visible data sectors on the disc. These aren't made anymore afaik, and an individual disc new-old stock on eBay starts at $15 (although I did find one cheaper in a bulk lot mixed with other DVD types). Would be a cool live backup, like a hard disk that's less damage prone, could also probably run and update an operating system (if I get one I'll try this).
- M-Disc: some sort of specially made disc that is write-once and rated to last 1000 years, available as DVD or BD. Needs a special type of M-Disc compatible drive for writing (and I think reading?) I barely looked into this, it just sounds expensive, lol. Good for immortalising My Immortal.
Let's Talk Longevity
There is mountains of information about this stuff all over the internet, some people decry an entire medium or format as 'unusable' depending on metal or dye type used, when in reality this equates to 'only' 20-50 years compared to 100+ years. I think it is important to not fall into a reddit frame of mind and just take time to determine how these numbers would relate to you. For me 20-50 years (numbers applied to basic CDs and DVDs) is more than enough as it provides SO MUCH time to take action and reburn stuff, and another fifty years is probably longer than I'll live, lmao.
Data Alchemy: If guaranteed longevity is desired or required, gold metal 'archival' DVDs are between $3-8 each in packs. The gold is far less prone to corrosion than the traditional silver DVDs and predicts a 100+ year lifespan, which isn't bad for the individual price, it's just that you need to outlay for packs of 5 ($30-40) to 50 ($150-200) to reach that price point.
Personal Example: I mentioned collecting a bunch of discs from my folks place earlier, so I can attest to the longevity of discs first-hand. Many of the burnt CDs I collected (worth focusing on as they have shorter lifespan than commerically pressed discs) were burned 20-30 years ago, and almost every single one read just fine. This includes the few blank CDs I found among them all that I have since written to in the past week (my webbed site here is backed up on an CD-RW produced in 1998). These were quality blanks for their time though, brands like Imation, Kodak Gold, and TDK, so that might have helped.
Maintenance: I encountered an issue with one unbranded burnt home-video DVD dated 2006. I could read and play the video fine, but wouldn't image properly when I tried to back it up. I noticed some marks that I assume were surface mould (there was a musty smell to some of the discs), and did a quick read of how to clean discs. Many places just recommend water and a microfibre cloth, one site mentioned isopropyl alcohol though and in a careless haste I didn't notice they specified 50/50 with water. I cleaned the disc with the 90% I had nearby and it stopped working, any drive I put it in would just spin until I manually pin-ejected it. I thennnnn read about cleaning it with toothpaste and figured I couldn't make it any worse. The toothpaste buff with a cloth followed by a rinse and gentle dry RESTORED THE DISC. I couldn't believe it, I always thought that was a myth. Just use a toothpaste that isn't 'whitening', they usually have microgranules that can scratch a disc further.
Storage: I'll note that the old discs I collected were just in a drawer with no special considerations taken in a 'temperate' region. Some discs come with their jewel cases, otherwise you can get a disc folder or dozens of plastic/paper sleeves pretty cheaply online or at discount stores. There are special purpose hard storage cases, but they come with a special purpose price. The metal in discs are able to be corroded by moisture, this is where gold discs are more useful, but still optical media was the preferred medium over tape in many humid regions. It may just take some time off the decades-long lifespan.
Preparation and Planning
Prep: Acquiring a drive; you probably already have at least one, otherwise online they can be lower than $30 used, with new ones like $50-100, you may even find a whole second hand PC with a drive in that price range though. Acquiring blanks; discount department stores, stationary stores, electronics stores, online sellers, even thrift stores sometimes have sealed blanks.
Planning/Organizing: Arguably the worst part about this is the planning required to fit large amounts of modern data into the storage capacity blocs of discs (700MB, 4.7GB, 8.5GB). It's still fine for me, as the money saved is being exchanged for my worthless time, lmao. I already mentioned earlier, CDs are good for audio, photos, and documents, while DVDs are better for higher def photos and videos. It's just a matter of grouping stuff together in a way that works, so you can look at a disc and clearly know what's on it. Stuff like grouping photos by year, documents by utility (say 'emails' or 'tax receipts'). Video is a bit harder, it really depends on the definition and file type, I can't think of any individual file that would be larger than a dual layer DVD though. It probably isn't feasible to backup a whole collection of terabytes of legally acquired backups of films and television, but maybe it would be worth it to save your absolute favourite stuff. I plan to do this with my fav 90s-00s sci fi shows, which I mostly seem to have in 720-1080p and .mkv anyway (an episode rarely breaks a GB). For this use case I'm luckily not a HD-UHD-4K person, as I don't think DVDs would be a worthwhile way to back up that magnitude of data.
I plan to maybe get through more video and music after copying my favourite stuff, even if it is a slow and tedious process over months-years, it will give me a chance to go through what I have. I also want to use discs as a means to share stuff with friends. Was thinking about this for a while, it might just be a more engaging way than stuff like ftp or jellyfin, with the end product being a physical copy they get to keep compared to the ephemeral space taken up on a harddrive. Mailing a disc (in a case or hard cardboard) is also a lower risk and cost than sending a flash or hard drive. I will create a siblinghood of the travelling... cracked games or whatever
Anyway, that's my mind empty now. Thanks for reading!