UEFI

This guide can be used to install Alpine onto a single disk with with or without ZFS encryption.

It assumes the following:

• Your system uses UEFI to boot

• Your system is x86_64

• You're mildly comfortable with ZFS, EFI and discovering system facts on your own (lsblk, dmesg, gdisk, ...)

Download the latest Alpine Extended ISO, write it to USB drive and boot your system in EFI mode.

Confirm EFI support:

# dmesg | grep -i efivars
[    0.301784] Registered efivars operations

Configure Live Environment

Source /etc/os-release

The file /etc/os-release defines variables that describe the running distribution. In particular, the $ID variable defined within can be used as a short name for the filesystem that will hold this installation.

source /etc/os-release
export ID

Add package repositories

cat <<EOF > /etc/apk/repositories
http://dl-cdn.alpinelinux.org/alpine/latest-stable/main/
https://dl-cdn.alpinelinux.org/alpine/latest-stable/main/
EOF
apk update

Setup additional tools

apk add zfs zfs-scripts sgdisk wipefs
modprobe zfs

Generate /etc/hostid

zgenhostid -f 0x00bab10c

Define disk variables

For convenience and to reduce the likelihood of errors, set environment variables that refer to the devices that will be configured during the setup.

For many users, it is most convenient to place boot files (i.e., ZFSBootMenu and any loader responsible for launching it) on the the same disk that will hold the ZFS pool. However, some users may wish to dedicate an entire disk to the ZFS pool or create a multi-disk pool. A USB flash drive provides a convenient location for the boot partition. Fortunately, this alternative configuration is easily realized by simply defining a few environment variables differently.

Verify your target disk devices with lsblk. /dev/sda, /dev/sdb and /dev/nvme0n1 used below are examples.

First, define variables that refer to the disk and partition number that will hold boot files:

Single SATA DiskSingle NVMe DiskSeparate Boot Device

export BOOT_DISK="/dev/sda"
export BOOT_PART="1"
export BOOT_DEVICE="${BOOT_DISK}${BOOT_PART}"

Next, define variables that refer to the disk and partition number that will hold the ZFS pool:

Single SATA DiskSingle NVMe DiskSeparate Boot Device

export POOL_DISK="/dev/sda"
export POOL_PART="2"
export POOL_DEVICE="${POOL_DISK}${POOL_PART}"

Disk preparation

Wipe partitions

wipefs -a "$POOL_DISK"
wipefs -a "$BOOT_DISK"

sgdisk --zap-all "$POOL_DISK"
sgdisk --zap-all "$BOOT_DISK"

zpool labelclear -f "$POOL_DISK"

Create EFI boot partition

sgdisk -n "${BOOT_PART}:1m:+512m" -t "${BOOT_PART}:ef00" "$BOOT_DISK"

Create zpool partition

sgdisk -n "${POOL_PART}:0:-10m" -t "${POOL_PART}:bf00" "$POOL_DISK"

Rescan Device Nodes

mdev -s

ZFS pool creation

Create the zpool

UnencryptedEncrypted

zpool create -f -o ashift=12 \
 -O compression=lz4 \
 -O acltype=posixacl \
 -O xattr=sa \
 -O relatime=on \
 -o autotrim=on \
 -o compatibility=openzfs-2.1-linux \
 -m none zroot "$POOL_DEVICE"

Note

The option -o compatibility=openzfs-2.1-linux ensures that the pool is created only with feature flags supported by the current ZFSBootMenu binary release. If you plan on building a custom ZFSBootMenu image that you will keep synchronized with your host, the compatibility option may be omitted.

Binary releases of ZFSBootMenu are generally built with the latest stable version of ZFS. Future releases of ZFSBootMenu may therefore support newer feature sets. Check project release notes prior to updating or removing compatibility options and upgrading your system pool.

Create initial file systems

zfs create -o mountpoint=none zroot/ROOT
zfs create -o mountpoint=/ -o canmount=noauto zroot/ROOT/${ID}
zfs create -o mountpoint=/home zroot/home

zpool set bootfs=zroot/ROOT/${ID} zroot

Note

It is important to set the property canmount=noauto on any file systems with mountpoint=/ (that is, on any additional boot environments you create). Without this property, the OS will attempt to automount all ZFS file systems and fail when multiple file systems attempt to mount at /; this will prevent your system from booting. Automatic mounting of / is not required because the root file system is explicitly mounted in the boot process.

Also note that, unlike many ZFS properties, canmount is not inheritable. Therefore, setting canmount=noauto on zroot/ROOT is not sufficient, as any subsequent boot environments you create will default to canmount=on. It is necessary to explicitly set the canmount=noauto on every boot environment you create.

Export, then re-import with a temporary mountpoint of /mnt

UnencryptedEncrypted

zpool export zroot
zpool import -N -R /mnt zroot
zfs mount zroot/ROOT/${ID}
zfs mount zroot/home

Verify that everything is mounted correctly

# mount | grep mnt
zroot/ROOT/alpine on /mnt type zfs (rw,relatime,xattr,posixacl)
zroot/home on /mnt/home type zfs (rw,relatime,xattr,posixacl)

Install Alpine

apk --arch x86_64 -X http://dl-cdn.alpinelinux.org/alpine/latest-stable/main \
 -U --allow-untrusted --root /mnt --initdb add alpine-base

Copy our files into the new install

UnencryptedEncrypted

cp /etc/hostid /mnt/etc
cp /etc/resolv.conf /mnt/etc
cp /etc/apk/repositories /mnt/etc/apk
cp /etc/network/interfaces /mnt/etc/network

Chroot into the new OS

mount --rbind /dev /mnt/dev
mount --rbind /sys /mnt/sys
mount --rbind /proc /mnt/proc
chroot /mnt

Set a root password

passwd

Enable startup targets

rc-update add hwdrivers sysinit
rc-update add networking
rc-update add hostname

ZFS Configuration

Install ZFS

apk add zfs zfs-lts
rc-update add zfs-import sysinit
rc-update add zfs-mount sysinit

Configure mkinitfs to load ZFS support

UnencryptedEncrypted

echo "/etc/hostid" >> /etc/mkinitfs/features.d/zfshost.files
echo 'features="ata base keymap kms mmc scsi usb virtio zfs zfshost"' > /etc/mkinitfs/mkinitfs.conf

Regenerate initramfs

mkinitfs -c /etc/mkinitfs/mkinitfs.conf "$(ls /lib/modules)"

Install and configure ZFSBootMenu

Set ZFSBootMenu properties on datasets

UnencryptedEncrypted

Assign command-line arguments to be used when booting the final kernel. Because ZFS properties are inherited, assign the common properties to the ROOT dataset so all children will inherit common arguments by default.

zfs set org.zfsbootmenu:commandline="quiet loglevel=4" zroot/ROOT

Create a vfat filesystem

mkfs.vfat -F32 "$BOOT_DEVICE"

Create an fstab entry and mount

cat << EOF >> /etc/fstab
$BOOT_DEVICE /boot/efi vfat defaults 0 0
EOF

mkdir -p /boot/efi
mount /boot/efi

Install ZFSBootMenu

Prebuilt

apk add curl

Fetch a prebuilt ZFSBootMenu EFI executable, saving it to the EFI system partition:

mkdir -p /boot/efi/EFI/ZBM
curl -o /boot/efi/EFI/ZBM/VMLINUZ.EFI -L https://get.zfsbootmenu.org/efi
cp /boot/efi/EFI/ZBM/VMLINUZ.EFI /boot/efi/EFI/ZBM/VMLINUZ-BACKUP.EFI

Configure EFI boot entries

DirectrEFInd

apk add efibootmgr

efibootmgr -c -d "$BOOT_DISK" -p "$BOOT_PART" \
  -L "ZFSBootMenu (Backup)" \
  -l '\EFI\ZBM\VMLINUZ-BACKUP.EFI'

efibootmgr -c -d "$BOOT_DISK" -p "$BOOT_PART" \
  -L "ZFSBootMenu" \
  -l '\EFI\ZBM\VMLINUZ.EFI'

See also

Some systems can have issues with EFI boot entries. If you reboot and do not see the above entries in your EFI selection screen (usually accessible through an F key during POST), you might need to use a well-known EFI file name. See Portable EFI for help with this. Your existing ESP can be used, in place of an external USB drive.

Refer to zbm-kcl.8 and zfsbootmenu.7 for details on configuring the boot-time behavior of ZFSBootMenu.

Prepare for first boot

Exit the chroot, unmount everything

exit

cut -f2 -d" " /proc/mounts | grep ^/mnt | tac | while read i; do umount -l $i; done

Export the zpool and reboot

zpool export zroot
reboot