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@andaag
Created April 19, 2020 13:12
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#cat /usr/share/ubiquity/zsys-setup
#!/bin/sh
#
# This script creates ZFS pools and dataset compatible with zsys
#
# Layout:
# bpool/BOOT/ubuntu_${UUID}
# rpool/ROOT/ubuntu_${UUID}
# rpool/ROOT/ubuntu_${UUID}/var -o canmount=off
# rpool/ROOT/ubuntu_${UUID}/var/games
# rpool/ROOT/ubuntu_${UUID}/var/lib
# rpool/ROOT/ubuntu_${UUID}/var/lib/AccountServices
# rpool/ROOT/ubuntu_${UUID}/var/lib/apt
# rpool/ROOT/ubuntu_${UUID}/var/lib/dpkg
# rpool/ROOT/ubuntu_${UUID}/var/log
# rpool/ROOT/ubuntu_${UUID}/var/mail
# rpool/ROOT/ubuntu_${UUID}/var/snap
# rpool/ROOT/ubuntu_${UUID}/var/spool
# rpool/ROOT/ubuntu_${UUID}/var/www
# rpool/ROOT/ubuntu_${UUID}/var/lib/NetworkManager
# rpool/ROOT/ubuntu_${UUID}/srv
# rpool/ROOT/ubuntu_${UUID}/usr -o canmount=off
# rpool/ROOT/ubuntu_${UUID}/usr/local
# rpool/USERDATA/$user_$UUID2
# rpool/USERDATA/root_$UUID2
#
# Steps:
# - Verify that /target is mounted
# - Retrieve fstab
# - unmount /target
# - delete all the partitions but the ESP
# - Create p1 ext4 size 100MB
# - Create p2 zfs bpool 1GB
# - Create p3 zfs rbool 100% remaining
# - Create datasets
# - Create /swapfile on /target
#
# After setup is done leave it mounted to let Ubiquity proceed with installation
set -eu
REQUIREDPKGS="zfsutils-linux"
TARGET="/target"
ESP="${TARGET}/boot/efi"
ZSYSTMP="/tmp/$(basename $0)"
INIT_FLAG="${ZSYSTMP}/init.done"
FSTAB_PARTMAN="${ZSYSTMP}/fstab.partman"
PARTITION_LAYOUT="${ZSYSTMP}/layout"
mkdir -p "${ZSYSTMP}"
usage() {
# Display script usage
cat<<EOF
Usage: $(basename "$0") [COMMAND] [OPTIONS...]
Prepares a zsys compatible ZFS system.
Commands:
layout Get layout to display before formatting to ubiquity. Give the chosen disk as argument
init Initialize the pools and datasets
finalize Finalize the installation after the system has been installed
Options:
-h, --help This help
-d, --debug Enable debug mode
EOF
exit
}
SHORTOPTS="hd"
LONGOPTS="help,debug"
TEMP=$(getopt -o $SHORTOPTS --long $LONGOPTS -- "$@")
eval set -- "$TEMP"
while true ; do
case "$1" in
-h|--help)
usage;;
-d|--debug)
set -x
shift;;
--)
shift;
break;;
*)
usage;;
esac
done
COMMAND=$( echo $1| tr '[:upper:]' '[:lower:]' )
EXTRAARG=""
if [ $# -gt 1 ]; then
EXTRAARG="${2}"
fi
check_prerequisites() {
# Check and set requirements to run this script
#
# Check and set the requirements to run this test. If any of the
# requirement is missing the programs exit with error
#
# Args:
# $@: List of required packages
#
# Returns
# Exit program is a requirement is not met
echo "I: Checking system requirements"
if [ $(id -u) -ne 0 ]; then
echo "E: Script must be executed as root. Exiting!"
exit 1
fi
for pkg in $@; do
if ! dpkg-query -W -f'${Status}' "${pkg}"|grep -q "install ok installed" 2>/dev/null; then
echo "E: $pkg is required and not installed on this system. Exiting!"
exit 1
fi
done
}
prepare_target() {
target="$1"
if ! grep -qE "\s${target}\s" /proc/mounts; then
echo "E: $target is not mounted. Exiting!"
exit 1
fi
# Save fstab generated by partman
if [ -f "${target}/etc/fstab" ]; then
echo "I: Saving existing fstab"
cp "${target}/etc/fstab" "${FSTAB_PARTMAN}"
else
echo "W: ${target}/etc/fstab doesn't exist"
fi
# umount /target
# It may fail to umount because the swap is being created by partman and not finished when we reach this point.
# Give it some time and retry with a sleep between tries.
iter=0
maxiter=10
for mountpoint in "${ESP}" "${target}"; do
if [ ! -d "${mountpoint}" ]; then
continue
fi
echo "I: umounting ${mountpoint}"
while :; do
# Do not make it quiet. We want to know why it failed.
if ! sudo umount "${mountpoint}"; then
iter=$(( iter + 1 ))
echo "W: Try ${iter}. Failed to umount ${mountpoint}."
if [ ${iter} -eq ${maxiter} ]; then
echo "E: Failed to umount ${mountpoint}. Exiting!"
exit 1
fi
sleep 3
else
break
fi
done
done
}
get_layout() {
# Returns disk, base name of the partition and partition numbers to create
target="$1"
disk="$2"
if [ -z "${disk}" ]; then
# The entire disk has been formatted with use_device
# There is either one ext4 partition or one ext4 and one ESP
part="$(grep -E "\s${target}\s" /proc/mounts | awk '{print $1}')"
partbase=""
if [ -n "${part}" ]; then
disk="$(lsblk -lns -o TYPE,PATH ${part}| grep disk| awk '{print $2}')"
if [ -z "${disk}" ]; then
echo "E: Couldn't identify disk for partition ${part}. Exiting!"
exit 1
fi
# Some disks have letters in the partition number like /dev/nvme0n1p1
# In this case we want to retrieve 'p' so we deal only with partition number
# in the rest of the script and prepend the base.
partbase="$(echo ${part} | sed -e 's/[0-9]*$//' | sed -e "s#${disk}##")"
fi
else
# The only purpose of this code is to display a friendly message in ubiquity to show the user
# what partitioning will be performed. However, on first call, the disk is not yet partitioned
# and collecting the information about disk partitioning would require to query partman. But we
# don't want to add this extra complexity just to display a message. Instead we hardcode the
# extension of the partition name depending on the type of disk, basically it's 'p' for anything
# else than standard drives (eg nvme01pX)
case "${disk}" in
/dev/sd*|/dev/hd*|/dev/vd*)
partbase=""
;;
*)
partbase="p"
esac
fi
partesp=1
if is_gpt "${disk}"; then
# No extended partition on EFI + GPT
# The layout is
# 1: ESP
# 2: swap
# 3: bpool
# 4: rpool
partswap=2
partbpool=3
partrpool=4
else
# MBR pools are on extended partition
# The layout is:
# 1: ESP
# 2: Extended
# 5: swap
# 6: bpool
# 7: rpool
partswap=5
partbpool=6
partrpool=7
fi
echo "OK|${disk}|${partbase}|${partesp}|${partswap}|${partbpool}|${partrpool}"
}
format_disk() {
disk="$1"
partbase="$2"
partesp="$3"
partbpool="$4"
partrpool="$5"
ss="$6"
partswap=$(( partbpool - 1 ))
partext=$(( partesp + 1 ))
partprefix="${disk}${partbase}"
sfdisktmp="${ZSYSTMP}/sfdisk.cfg"
rm -f "${sfdisktmp}"
echo "I: Formatting disk $disk with partitions ESP:${partesp} ext:${partext} swap:${partswap} bpool:${partbpool} rpool:${partrpool}"
# bpool size: 500M < 5% of ZFS allocated space < 2G
# partswap is partition 2 on GPT systems and first extended partition on MBR.
size_percent=$(expr \( $(blockdev --getsize64 ${partprefix}${partswap}) / 1024 / 1024 \) \* 5 / 100)
bpool_size=500
[ ${size_percent} -gt ${bpool_size} ] && bpool_size=${size_percent}
[ ${bpool_size} -gt 2048 ] && bpool_size=2048
if is_gpt "${disk}"; then
# Improvement: Delete all the partitions but the ESP
# There should be only 1 or 2 partitions but it can be made generic
if ! esp_exists "${disk}"; then
start=$(sfdisk -l "${disk}"|grep "^${partprefix}${partesp}"|awk '{print $2}')
cat > "${sfdisktmp}" <<EOF
${partprefix}${partesp} : start= ${start}, size= 512M, type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, bootable
EOF
else
sfdisk --delete "${disk}" ${partswap}
fi
cat >> "${sfdisktmp}" <<EOF
${partprefix}${partswap} : size= ${ss}M, type=0657FD6D-A4AB-43C4-84E5-0933C84B4F4F
${partprefix}${partbpool} : size= ${bpool_size}M, type=6A82CB45-1DD2-11B2-99A6-080020736631
${partprefix}${partrpool} : type=6A85CF4D-1DD2-11B2-99A6-080020736631
EOF
else
if ! esp_exists "${disk}"; then
start=$(sfdisk -l "${disk}"|grep "^${partprefix}${partesp}"|awk '{print $2}')
cat > "${sfdisktmp}" <<EOF
${partprefix}${partesp} : start= ${start}, size= 512M, type=ef, bootable
EOF
else
sfdisk --delete "${disk}" ${partswap}
fi
cat >> "${sfdisktmp}" <<EOF
${partprefix}${partswap} : size= ${ss}M, type=82
${partprefix}${partbpool} : size= ${bpool_size}M, type=a5
${partprefix}${partrpool} : type=a5
EOF
fi
cat "${sfdisktmp}" | sfdisk --append "${disk}"
# Force a re-read of the partition table
echo "I: Re-reading partition table"
partx --add "${disk}" 2>/dev/null || true
partx --show "${disk}"
}
init_zfs() {
target="$1"
partbpool="$2"
partrpool="$3"
echo "I: Initializing ZFS"
# Now we can create the pools and dataset
UUID_ORIG=$(head -100 /dev/urandom | tr -dc 'a-z0-9' |head -c6)
# Pools
# rpool
zpool create -f \
-o ashift=12 \
-O compression=lz4 \
-O acltype=posixacl \
-O xattr=sa \
-O relatime=on \
-O normalization=formD \
-O mountpoint=/ \
-O canmount=off \
-O dnodesize=auto \
-O sync=disabled \
-O mountpoint=/ -R "${target}" rpool "${partrpool}"
# bpool
# The version of bpool is set to the default version to prevent users from upgrading
# Then only features supported by grub are enabled.
zpool create -f \
-o ashift=12 \
-d \
-o feature@async_destroy=enabled \
-o feature@bookmarks=enabled \
-o feature@embedded_data=enabled \
-o feature@empty_bpobj=enabled \
-o feature@enabled_txg=enabled \
-o feature@extensible_dataset=enabled \
-o feature@filesystem_limits=enabled \
-o feature@hole_birth=enabled \
-o feature@large_blocks=enabled \
-o feature@lz4_compress=enabled \
-o feature@spacemap_histogram=enabled \
-O compression=lz4 \
-O acltype=posixacl \
-O xattr=sa \
-O relatime=on \
-O normalization=formD \
-O canmount=off \
-O devices=off \
-O mountpoint=/boot -R "${target}" bpool "${partbpool}"
# Root and boot dataset
zfs create rpool/ROOT -o canmount=off -o mountpoint=none
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}" -o mountpoint=/
zfs create bpool/BOOT -o canmount=off -o mountpoint=none
zfs create "bpool/BOOT/ubuntu_${UUID_ORIG}" -o mountpoint=/boot
# System dataset
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var" -o canmount=off
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/lib"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/lib/AccountServices"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/lib/apt"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/lib/dpkg"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/lib/NetworkManager"
# Desktop specific system dataset
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/srv"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/usr" -o canmount=off
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/usr/local"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/games"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/log"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/mail"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/snap"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/spool"
zfs create "rpool/ROOT/ubuntu_${UUID_ORIG}/var/www"
# USERDATA datasets
# Dataset associated to the user are created by the installer.
zfs create rpool/USERDATA -o canmount=off -o mountpoint=/
# Set zsys properties
zfs set com.ubuntu.zsys:bootfs='yes' "rpool/ROOT/ubuntu_${UUID_ORIG}"
zfs set com.ubuntu.zsys:last-used=$(date +%s) "rpool/ROOT/ubuntu_${UUID_ORIG}"
zfs set com.ubuntu.zsys:bootfs='no' "rpool/ROOT/ubuntu_${UUID_ORIG}/srv"
zfs set com.ubuntu.zsys:bootfs='no' "rpool/ROOT/ubuntu_${UUID_ORIG}/usr"
zfs set com.ubuntu.zsys:bootfs='no' "rpool/ROOT/ubuntu_${UUID_ORIG}/var"
}
move_user () {
target="$1"
user="$2"
userhome="$3"
uuid="$4"
echo "I: Creating user $user with home $userhome"
mv "${target}/${userhome}" "${target}/tmp/home/${user}"
zfs create "rpool/USERDATA/${user}_${uuid}" -o canmount=on -o mountpoint=${userhome}
chown $(chroot "${target}" id -u ${user}):$(chroot ${target} id -g ${user}) "${target}/${userhome}"
rsync -a "${target}/tmp/home/${user}/" "${target}/${userhome}"
bootfsdataset=$(grep "\s${target}\s" /proc/mounts | awk '{ print $1 }')
zfs set com.ubuntu.zsys:bootfs-datasets="${bootfsdataset}" rpool/USERDATA/${user}_${UUID_ORIG}
}
init_system_partitions() {
target="$1"
partefi="$2"
partgrub="$3"
# ESP
mkdir -p "${target}/boot/efi"
mount -t vfat "${partefi}" "${target}/boot/efi"
mkdir -p "${target}/boot/efi/grub"
echo "I: Mount grub directory"
# Finalize grub directory
mkdir -p "${target}/boot/grub"
mount -o bind "${target}/boot/efi/grub" "${target}/boot/grub"
}
esp_exists() {
if is_gpt "${1}"; then
parttype="C12A7328-F81F-11D2-BA4B-00A0C93EC93B"
else
# FIXME: Currently partman-auto set the type of EFI on MBR as W95 (b) instead of EFI (ef)
parttype="b"
fi
sfdisk -d "${1}" | grep -q "type=${parttype}"
}
is_gpt() {
sfdisk -d "${1}" | awk '/^label:/ {print $2}'|grep -q gpt
}
check_prerequisites ${REQUIREDPKGS}
echo "I: Running $(basename "$0") ${COMMAND}"
if [ -z "${COMMAND}" ]; then
echo "E: ${COMMAND} is mandatory. Exiting!"
exit 1
elif [ "${COMMAND}" = "layout" ]; then
# Just displays de layout that will be created without any change to the disk.
# At this stage we don't now yet the size of the partition that will be created.
IFS="|" read ERR DISK PARTBASE PARTESP PARTSWAP PARTBPOOL PARTRPOOL<<EOF
$(get_layout ${TARGET} "${EXTRAARG}")
EOF
if [ "${ERR}" != "OK" ]; then
echo "${ERR}"
exit 1
fi
cat > "${PARTITION_LAYOUT}" <<EOF
disk:${DISK}
EOF
if ! esp_exists "${DISK}"; then
cat >> "${PARTITION_LAYOUT}" <<EOF
part:vfat:ESP:${DISK}${PARTBASE}${PARTESP}
EOF
fi
cat >> "${PARTITION_LAYOUT}" <<EOF
part:swap:swap:${DISK}${PARTBASE}${PARTSWAP}
part:zfs:bpool:${DISK}${PARTBASE}${PARTBPOOL}
part:zfs:rpool:${DISK}${PARTBASE}${PARTRPOOL}
EOF
elif [ "${COMMAND}" = "init" ]; then
rm -f "${INIT_FLAG}"
IFS="|" read ERR DISK PARTBASE PARTESP PARTSWAP PARTBPOOL PARTRPOOL<<EOF
$(get_layout ${TARGET} "")
EOF
if [ "${ERR}" != "OK" ]; then
echo "${ERR}"
exit 1
fi
echo "I: Partition table before init of ZFS"
partx --show "${DISK}"
# Swap files are not supported on ZFS, we use a swap partition instead:
SWAPFILE="$(grep "^${TARGET}" /proc/swaps |awk '{print $1}')"
# Give us a minimum swap partition size of 4MB in case we decide on
# no swap, just to keep the partition layout stable:
SWAPSIZE=4194304
# Disable swap and get the swap volume size:
if [ -n "${SWAPFILE}" ]; then
SWAPSIZE=$(stat -c%s "${SWAPFILE}")
echo "I: Found swapfile with size ${SWAPSIZE}. Disabling"
swapoff "${SWAPFILE}"
fi
# Convert to MiB to align the size on the size of a block
SWAPVOLSIZE=$(( SWAPSIZE / 1024 / 1024 ))
prepare_target "${TARGET}"
format_disk "${DISK}" "${PARTBASE}" "${PARTESP}" "${PARTBPOOL}" "${PARTRPOOL}" "${SWAPVOLSIZE}"
init_zfs "${TARGET}" "${DISK}${PARTBASE}${PARTBPOOL}" "${DISK}${PARTBASE}${PARTRPOOL}"
init_system_partitions "${TARGET}" "${DISK}${PARTBASE}1" "${DISK}${PARTBASE}${PARTESP}"
# Generate fstab
# $TARGET/etc has been destroyed by the creation of the zfs partitition
# Recreate it
mkdir -p "${TARGET}/etc"
if [ -f "${FSTAB_PARTMAN}" ]; then
echo "I: Creating fstab"
grep -Ev '\s/\s|/swapfile' "${FSTAB_PARTMAN}" > "${TARGET}/etc/fstab"
fi
if ! grep -q "boot/efi" "${TARGET}/etc/fstab"; then
espuuid=$(blkid -s UUID -o value "${DISK}${PARTBASE}${PARTESP}")
echo "UUID=${espuuid}\t/boot/efi\tvfat\tumask=0077\t0\t1" >> "${TARGET}/etc/fstab"
fi
# Bind mount grub from ESP to the expected location
echo "/boot/efi/grub\t/boot/grub\tnone\tdefaults,bind\t0\t0" >> "${TARGET}/etc/fstab"
if [ -n "${SWAPFILE}" ]; then
SWAPDEVICE="${DISK}${PARTBASE}${PARTSWAP}"
mkswap -f "${SWAPDEVICE}"
SWAPID=$(blkid -s UUID -o value "${SWAPDEVICE}")
printf "UUID=${SWAPID}\tnone\tswap\tdiscard\t0\t0\n" >> "${TARGET}/etc/fstab"
swapon -v "${SWAPDEVICE}"
fi
echo "I: Marking ZFS utilities to be kept in the target system"
apt-install zfsutils-linux 2>/dev/null
apt-install zfs-initramfs 2>/dev/null
apt-install zsys 2>/dev/null
touch "$INIT_FLAG"
elif [ "${COMMAND}" = "finalize" ]; then
if [ ! -f "$INIT_FLAG" ]; then
echo "W: zsys init didn't succeed. Not proceeding with command: ${COMMAND}. Aborting!"
exit 1
fi
# Activate zfs generator.
# After enabling the generator we should run zfs set canmount=on DATASET
# in the chroot for one dataset of each pool to refresh the zfs cache.
echo "I: Activating zfs generator"
ln -s /usr/lib/zfs-linux/zed.d/history_event-zfs-list-cacher.sh "${TARGET}/etc/zfs/zed.d"
# Create zpool cache
zpool set cachefile= bpool
zpool set cachefile= rpool
cp /etc/zfs/zpool.cache "${TARGET}/etc/zfs/"
mkdir -p "${TARGET}/etc/zfs/zfs-list.cache"
touch "${TARGET}/etc/zfs/zfs-list.cache/bpool" "${TARGET}/etc/zfs/zfs-list.cache/rpool"
# Handle userdata
UUID_ORIG=$(head -100 /dev/urandom | tr -dc 'a-z0-9' |head -c6)
mkdir -p "${TARGET}/tmp/home"
for user in ${TARGET}/home/*; do
if [ -d "${user}" ]; then
user="$(basename $user)"
move_user "${TARGET}" "${user}" "/home/${user}" "${UUID_ORIG}"
fi
done
move_user "${TARGET}" root /root "${UUID_ORIG}"
echo "I: Changing sync mode of rpool to standard"
zfs set sync=standard rpool
echo "I: ZFS setup complete"
else
echo "E: Unknown command: $COMMAND"
exit 1
fi
@jze1
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jze1 commented Apr 1, 2021

#192: partbase="$(echo ${part} | sed -e 's/[0-9]*$//' | sed -e "s#${disk}##")"

is not working, with sed -e "s/${disk}//" it is.

@andaag
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Author

andaag commented Apr 2, 2021

That's, worrying, because that is copied from the standard ubuntu script. - at least it was standard at the first release, I'm guessing these have been improved by then.

@jze1
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jze1 commented Apr 4, 2021

Not yet in the last 20.04 update. I don't expect it to be fixed anyway as the whole zsys-setup is an ugly installation hack.

@paulatz
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paulatz commented Apr 14, 2022

Do you think it is not working, or do you have a use case where it does not work? Because the sed syntax you post is exactly equivalent to the one used in the script, but yours will fail if ${disk} contains any "/", which is guaranteed failure. On the other hand, the syntax used in the script will only fail if ${disk} contains a "#", which is less likely.

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