On Fri, Feb 13, 2015 at 7:31 PM, James <wireless@xxxxxxxxxxxxxxx> wrote: >No swap for now (each system had 32G) if I need > swap later, I can just setup a file and use swapon? No. You should read the wiki. https://btrfs.wiki.kernel.org/index.php/FAQ#Does_btrfs_support_swap_files.3F > What I want is if a drive fails, > I can just replace it, or pull one drive out, replace it with a second > blank, 2T new drive. Them move the removed drive into a second (identical) > system to build a cloned workstation. From what I've read, uuid numbers > are suppose to be use with fstab + btrfs Partuuid is still flaky. But the > UUID numbers to not appear uniq (due to raid-1)? Do the only get listed once > in fstab? Once is enough. Kernel code will find both devices. For degraded use, this gets tricky, you have to use boot param rootflags=degraded to get it to mount, otherwise mount fails and you'll be dropped to a pre-mount shell in the initramfs. Also, there's a nasty little gotcha, there is no equivalent for mdadm bitmap. So once one member drive is mounted degraded+rw, it's changed, and there's no way to "catch up" the other drive - if you reconnect, it might seem things are OK but there's a good chance of corruption in such a case. You have to make sure you wipe the "lost" drive (the older version one). wipefs -a should be sufficient, then use 'device add' and 'device delete missing' to rebuild it. This should not be formatted ext4, it's strictly for GRUB, it doesn't get a file system. You should use wipefs -a on this. This fstab has lots of problems. Based on your partition scheme it should only have two entries total. A btrfs /boot UUID="d67a... and a btrfs / UUID="b7753... There is no mountpoint for biosboot, it's used by GRUB and is never formatted or mounted. > First I notice the last partition (sdb1) seems to be missing the ext4 file > system I guess when I exit the chroot I can just fix that to match sda1. No the problem is sda1 is wrongly formatted ext4, you should use wipefs -a on it. > Any help or guidance would be keen, > to help salvage the installation and get a few partitions installed > with btrfs. Maybe I can somehow migrate to a raid-1 configuration > under btrfs. Good luck. Make backups often. Btrfs raid1 is not a backup. Btrfs snapshots are not a backup. And use recent kernels. Recent on this list means 3.18.3 or newer, and is listed unstable on this list http://packages.gentoo.org/package/sys-kernel/gentoo-sources Based on the kernel.org change log, you'd probably be fine running 3.14.31, but if you have problems and ask about it on this list, there's a decent chance the first question will be "can you reproduce the problem on a current kernel?" Anyway, I suggest reading the entire btrfs wiki. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
