Has anyone been able to install 21.05 on a ZFS root? My attempts have all failed. The message importing root ZFS pool "rpool"... appears and a long string of dots follows. Then It tries about 10 more times with mounting rpool/root/nixos on /mnt-root failed: no such file or directory and drops me into a menu with reboot immediately or ignore the error and continue. Neither rebooting nor continuing works.
I added boot_on_fail to the boot.kernelParams, which adds launch an interactive shell and start an interactive shell having pid1 options. I chose the first option to enter a shell. I am able to import the pool with:
# zpool import -f rpool
# mount -t zfs rpool/root/nixos /mnt-root
# exit
and it finished booting successfully. But the same problem occurs again when I reboot. Clearly something is preventing the root pool from being imported.
Any suggestions?
NB: I have been running ZFS root since at least 19.09 so I’m not a stranger to the process but this is the first time I’ve any problems. It has just worked in the past.
Details
I created the VM using the command:
$ virt-install --connect qemu:///system --virt-type kvm \
--name minimal-zfs --description "NixOS 21.05 minimal ZFS install" \
--os-type=linux --os-variant=none --machine q35 --sound ich9 \
--vcpus=1 --memory=2048 --rng /dev/random --boot uefi \
--graphics spice --video virtio --channel spicevmc \
--network network=default,model=virtio,mac=RANDOM \
--controller type=scsi,model=virtio-scsi,driver.iommu=on \
--boot hd,cdrom \
--disk device=disk,bus=virtio,format=qcow2,driver.discard=unmap,boot.order=1,path=/virt/images/nixos/minimal_zfs.qcow2,size=20 \
--disk device=cdrom,bus=scsi,readonly=on,boot.order=2,path=/virt/images/nixos/nixos-minimal-21.05.740.aa576357673-x86_64-linux.iso
I partitioned the virtual disk pretty much as shown in NixOS 23.11 manual | Nix & NixOS and https://nixos.wiki/wiki/NixOS_on_ZFS:
# parted -a optimal /dev/vda -- mklabel gpt
# parted -a optimal /dev/vda -- mkpart primary 512MiB -2GiB
# parted -a optimal /dev/vda -- mkpart primary linux-swap -2GiB 100%
# parted -a optimal /dev/vda -- mkpart ESP fat32 1MiB 512MiB
# parted -a optimal /dev/vda -- set 3 esp on
I created the pool with:
# zpool create \
-m none -o altroot=/mnt \
-o ashift=12 -o autotrim=on \
-O atime=off -O relatime=on \
-O compression=lz4 \
-O acltype=posixacl -O xattr=sa \
-O normalization=formD \
rpool /dev/vda1
created the datasets and mounted everything with:
# zfs create -p -o mountpoint=legacy rpool/root/nixos
# zpool set bootfs=rpool/root/nixos rpool
# mount -t zfs rpool/root/nixos /mnt
# mkfs.vfat -F 32 -n EFI /dev/vda3
# mkdir /mnt/boot
# mount /dev/vda3 /mnt/boot
# mkswap -L swap /dev/vda2
# swapon /dev/vda2
# zfs create -p -o mountpoint=legacy rpool/home
# mkdir /mnt/home
# mount -t zfs rpool/home /mnt/home
Next I generated the initial configuration with:
# nixos-generate-config --root /mnt
and modified configuration.nix to be:
{ config, pkgs, ... }:
{
imports = [
./hardware-configuration.nix
];
boot.loader.systemd-boot.enable = true;
boot.loader.efi.canTouchEfiVariables = true;
boot.initrd.supportedFilesystems = ["zfs"];
boot.supportedFilesystems = [ "zfs" ];
boot.kernelParams = [
"zfs.zfs_arc_max=1610612736" # 1.5GB
"boot.shell_on_fail" # insecure: no password required; use only for debugging
];
networking.hostId = "be798c19";
networking.useDHCP = false; # deprecated
networking.interfaces.enp1s0.useDHCP = true;
system.stateVersion = "21.05"; # man configuration.nix or https://nixos.org/nixos/options.html
}
then installed and rebooted:
nixos-install --root /mnt
shutdown -r now
