On 4/19/16, Nicholas D Steeves <nsteeves@xxxxxxxxx> wrote: .... > Is your flash drive formatted btrfs? If it is, you could always > snapshot it, send the snapshot to your array, set property of that > subvolume to RW, chroot, update fstab to mount / with the appropriate > subvol=option, update /etc/default/grub, reinstall grub and > update-grub, and reboot with your / as a subvolume on y> .... >I'm > in the process of documenting how to do this on the Debian wiki. > Please let me know if I should put a rush on it. It uses the subvol= > option rather than changing the volume's default subvol. > > Cheers, > Nicholas > First, I verified that while the Debian Installer will install to a pre set default BTRFS RAID6 subvolume, the Grub install step fails. The alternative to restore installation to a RAID6 subvolume requires installation to a non RAID6 subvolume and then send|receive the snapshotted installation to the array. To prepare for this attempt, I reinstalled BTRFS (Debian stable) to a flash drive using separate partitions for efi, /boot/ and / (in a subvolume). The default subvolume was set to 5 for both the flash / partition and also the RAID6 array. I used a separate /boot partition to reduce complexity. Both the kernel and btrfs tools were upgraded to 4.4. I soon thereafter got lost. The steps "snapshot it, send the snapshot to your array, set property of that subvolume to RW, chroot, update fstab to mount / with the appropriate subvol=option," posed no problem, then I got confused. Should the next step "update /etc/default/grub" be done within the chroot environment and what does "update /etc/default/grub" mean? I assume update=grub is done outside the grub environment because it fails to execute within the chroot/. What am I missing? Outside the chroot environment I did both an update-grub and a grub-install. My nas still boots using root on the flash drive. How do I fix this? I guess I am requesting that you "put a rush" on you documentation effort. I observe that "/boot/grub/grub.cfg" still references the flash drive root rather than the array root. The nas functions flawlessly but I would sleep better with root on the RAID6 array rather than on a flash drive. Both the efi and /boot partitions are almost read only so using cheap flash here is not a substantive risk. Thanks in advance: David Alcorn -- 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
