> In general, avoid Ubuntu LTS versions when dealing with BTRFS, as well as > most enterprise distros, they all tend to back-port patches instead of using > newer kernels, which means it's functionally impossible to provide good > support for them here (because we can't know for sure what exactly they've > back-ported). I'd suggest building your own kernel if possible, with Arch > Linux being a close second (they follow upstream very closely), followed by > Fedora and non-LTS Ubuntu.
Then I would build my own, if that is the preferred option. > Do not use BTRFS raid6 mode in production, it has at least 2 known serious > bugs that may cause complete loss of the array due to a disk failure. Both > of these issues have as of yet unknown trigger conditions, although they do > seem to occur more frequently with larger arrays. Ok. No raid6. > That said, there are other options. If you have enough disks, you can run > BTRFS raid1 on top of LVM or MD RAID5 or RAID6, which provides you with the > benefits of both. > > Alternatively, you could use BTRFS raid1 on top of LVM or MD RAID1, which > actually gets relatively decent performance and can provide even better > guarantees than RAID6 would (depending on how you set it up, you can lose a > lot more disks safely). If you go this way, I'd suggest setting up disks in > pairs at the lower level, and then just let BTRFS handle spanning the data > across disks (BTRFS raid1 mode keeps exactly two copies of each block). > While this is not quite as efficient as just doing LVM based RAID6 with a > traditional FS on top, it's also a lot easier to handle reshaping the array > on-line because of the device management in BTRFS itself. Right now I only have 10TB of backup data, but this is grow when urbackup is roled out. So maybe I could get a way with plain btrfs raid10 for the first year, and then re-balance to raid6 when the two bugs have been found... is the failed disk handling in btrfs raid10 considered stable? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
