On 03/07/17 13:21, Roderick wrote: > On Tue, 7 Mar 2017, Christian Weisgerber wrote: > >> On 2017-03-07, Roderick <hru...@gmail.com> wrote: >> >>> Disk are to be readable for many decades. Standard File System >>> readable after moving the Disks to another computer, different >>> hardware, perhaps with different OS. >> >> *uncontrollable laughter* > > Then you got, what is the problem. But it is not for laughing, it was > the escense of my question. > > I can read till now very old SCSI disks, also 3 1/2'' floppies, but > not always 5 1/4'' (because of the low level formatting). Of course, > depending on the file system. I would not use FAT, ufs would be a > good choice.
actually, I've had far better luck reading 5.25" floppies than old 3.5". Last time I checked my 8" floppies, they were doing better than the 5.25". In fact, I've got the gear to calibrate a 5.25" and 8" floppy drive -- you "repair" a 3.5" floppy drive with the trashcan. Which is great..assuming you can get a new one. Very old SCSI and IDE disks that made it five years usually made it a lot longer (and some never seem to die). However, I'm seeing a continued decline in long term product reliability as prices continue to plummet in the IT world. I really don't think you will be seeing ten year old 2TB SATA (or SAS) disks very often. (please don't quote MTBFs to me, it makes me laugh for a moment, and then I get sad when I realize people believe that shit) Technology changes. Hard to tell when. A number of years ago, I had an opportunity to buy a bunch of IDE to SCSI enclosures for really cheap. I ... uh ... loaded up. These things were great -- 16 IDE disks, attached to one SCSI port -- you could carve up the array into multiple virtual drives, and I was thinking, "wow...16 500G disks...that's a lot of storage! 1TB disks are coming soon, too!" Well, very shortly after I acquired the last of these things, the market turned, and SATA killed IDE. Only a few token IDE disks remained being produced, and they were EXPENSIVE compared to the SATAs. I found a cute little IDE to SATA adapter that actually fit in the array's trays, but then I quickly discovered that 1T was the limit of the array's disk handling abilities. Meanwhile, the rest of the world said, "What's SCSI?" -- finding something to plug the array into was becoming a trick. I.e., I loaded up on a lot of junk. And someone was freaking brilliant to know when to get OUT of that technology. The point is, you can't design ONE box for ten years of life. With modern SSD tech, I suspect you won't see a SATA port on a computer in ten years. What you need to do is have simple, reliable, and movable solutions, where the REPLACEMENT of the solution is part of it. Your desire to be able to move the disks from one computer to another is good -- when your base hw dies, you need to be able to transport your disks to something else. I can't think of another OS that does that better than OpenBSD. But you take that opportunity as a clue that maybe you need to update your tech, too. Build a simple solution with simple hw of today. When that hw starts getting old and looking rather "different" than newer hw, migrate. Your data is just data, that's what's important. The hw, the platform, the OS, can all be swapped out...AND SHOULD BE swapped out when appropriate. You ain't marrying your solution, quit trying to make it last longer than modern marriages last. A word on ZFS: I've used it. I've used a few features many people probably haven't. It's got a lot of features. It has a huge number of knobs. It's about as anti-OpenBSD as I can imagine, and I'm not talking about the license. It is about as far from "Just Works" as you can get a file system to be anymore. I had a friend tell me once how he'd never want to run a database on anything OTHER than ZFS because of all the file system integrity features. Then he admitted how many times the system crashed on him... Um. crashes for databases are bad, file system magic doesn't change that. My experience with ZFS was that it had the stability of a pig on stilts, and not much more grace. In many ways, ZFS seems to me to be a throwback to the 1980s when file systems needed to be "tuned" and maintained. Your opinion may vary. I know some people who's opinion I respect a lot that think ZFS is the greatest thing ever. I just disagree on that point. Note: OpenBSD's softraid supports three disk RAID1. A lot of people don't understand that -- it's THREE copies of your data. Lose a disk, you still got TWO copies to rebuild from. So my recommendation would be a simple solution that will fit you for maybe two or three years, maybe three disk RAID1, and every two or three years look at your system and the alternatives out there and ask if it makes sense to upgrade now or wait a year or two. Move your data to a new system when appropriate, asking yourself each time, "what's a good solution NOW?". And have an off-site rotated backup of all your data. Nick.
