On 24/11/2022 21:10, David T-G wrote:
How is linear different from RAID0? I took a quick look but don't quite know what I'm reading. If that's better then, hey, I'd try it (or at least learn more).
Linear tacks one drive on to the end of another. Raid-0 stripes across all drives. Both effectively combine a bunch of drives into one big drive.
Striped gives you speed, a big file gets spread over all the drives. The problem, of course, is that losing one drive can easily trash pretty much every big file on the array, irretrievably.
Linear means that much of your array can be recovered if a drive fails. But it's no faster than a single drive because pretty much every file is stored on just the one drive. And depending on what drive you lose, it can wipe your directory structure such that you just end up with a massive lost+found directory.
That's why there's raid-10. Note that outside of Linux (and often inside) when people say "raid-10" they actually mean "raid 1+0". That's two striped raid-0's, mirrored.
Linux raid-10 is different. it means you have at least two copies of each stripe, smeared across all the disks.
Either version (10, or 1+0), gives you get the speed of striping, and the safety of a mirror. 10, however, can use an odd number of disks, and disks of random sizes.
Cheers, Wol
