On Fri, 24 Jul 2015 at 21:07 James Harper <james@ejbdigital.com.au> wrote:
I had that happen occasionally, but in my case when btrfs failed to mount it was because the disk never started up at all, and it was always the same disk.
Yes, that would make more sense.
Are the disks in question spun up by the BIOS, or by Linux?
Not sure. I would have assumed BIOS spins all the disks up it detects before starting grub. I am not exactly keeping up with modern BIOS trends though (it is UEFI boot), so I could be wrong here. The disks containing the btrfs partitions are not used for booting, and are not used for / either.
Is it always the same disk, or a different disk each time?
Same disk, which isn't terribly surprising - I only have one btrfs. It is RAID1, however I refer to /dev/sdb1 in /etc/fstab - which should automatically bring in /dev/sdc1 if my understanding is correct. I am very doubtful it is btrfs' fault, it seems very odd regardless that I only encountered hard failures after converting to btrfs.