[Pkg-zfsonlinux-devel] zfsutils-linux: /usr/sbin/grub-probe: error: unknown filesystem

[Craig Sanders]

On Sat, Nov 05, 2016 at 08:20:38PM +0800, Aron Xu wrote:
> There is not yet a simple way to setup ZFS as rootfs in Debian because
> grub2 package is still missing the relevant support even in Sid.

The main problem with grub2 and zfs on debian is that grub-probe only
looks in /dev for the devices used by a vdev, not in /dev/disk/by-id/

I ran into that issue when I converted some of my machines to zfs rootfs. 

A workaround is to make symlinks in /dev that link to the correct device
node (or to the symlinks in /dev/disk/by-id).

e.g. if your rootfs is on Crucial SSDs as mine are:

    cd /dev
    ln -s /dev/disk/by-id/Crucial* .

you will also need to add a udev rule (or use /etc/rc.local) to recreate
those symlinks on every boot, so that running 'update-grub' works.

for my notes on converting an existing debian system, see:

http://blog.taz.net.au/2016/10/09/converting-to-a-zfs-rootfs/


This can be used for new systems too - just do an initial base system
install, install packages (incl. zfs-dkms and kernel headers), convert
it to root on zfs, and then install whatever else you need.  Not as
convenient as being integrated into DI but still useful.

You can even install to a single ext4 disk or partition, create a
non-mirrored root pool and rsync, chroot, grub-install etc, and when
you've successfully booted on that, add the original disk to the pool as
a mirror.

Or just use any old spare disk for the initial install - it only has to
be big enough for debian base + build-essential etc + kernel headers +
zfs/spl packages. a USB stick would be slow but should work.

craig

--
craig sanders <cas at taz.net.au>