I have backups on a backup hard drive and also synced to B2, but I am thinking about backing up to some format to put in the cupboard.
The issue I see is that if I don’t have a catastrophic failure and instead just accidentally delete some files one day while organising and don’t realise, at some point the oldest backup state is removed and the files are gone.
The other thing is if I get hit by a bus and no one can work out how to decrypt a backup or whatever.
So I’m thinking of a plain old unencrypted copy of photos etc that anyone could find and use. Bonus points if I can just do a new CD or whatever each year with additions.
I have about 700GB of photos and videos which is the main content I’m concerned about. Do people use DVDs for this or is there something bigger? I am adding 60GB or more each year, would be nice to do one annual addition or something like that.
ZFS with automatic snapshots and scrubbing. This will keep as many and as old snapshots as your like. It’ll ensure the files don’t rot. It’ll ensure the media doesn’t die, so long as you have enough redundancy and you replace disks as they die. This is what I’d trust for long term storage because I think I understand how and why it works. It should last as long as I feed it disks. If I delete something, I should be able to restore it from a snapshot. The hardware doesn’t need to be anything fancy. Just a Pi 4/5 with a couple of WD Elements would be fine. Could add more disks for more redudnancy. I’m running 2-disk residency.
You don’t have to touch the software if it’s not exposed to the Internet. Whatever works today on it will work 20 years from now, so long as the hardware works. A couple of spare Pis, SD cards and power supplies should let it last for decades.
I’d rather cold storage but am thinking of looking along these lines, ZFS or btrfs on a standard HDD that I add files on to once a year and replace the disk every few years.
I have a standard backup setup I just want something that is more point in time and not connected to all the automation, in case I automatically delete everything.
Yup, turn it on, let it do a scrub, then turn it off. I’d still use redudnancy though. Not merely to cover the case of the drive failing, but also to cover the bit rot use case. It’s exceedingly unlikely bits to rot at the exact same spot on two or more disks. When ZFS finds a checksum mismatch during a scrub (which indicates bit rot), it’ll be able to trivially recover the data from the drive where the checksum matches. It’ll then rewrite the rotten part.
Would that be two disks under a type of RAID or does ZFS have something?
With 2 disks that would be type mirror in ZFS-speak, completely built-in. Equivalent to RAID1 in terms of hardware fault tolerance.
You could do a 3-disk mirror or n-disk mirror really. The RAID5/6 rough equivalents are called RAIDzN where N is the number of disk failures they tolerate. E g. RAIDz1, RAIDz2, etc. You probably want a mirror unless you need more space than a single disk provides.
Ah thanks, that gives me something to research.