Skrypt w Bashu - system plików ZFS

Co poprawić w tym skrypcie? Czy mam pisać skrypty tak by były zgodne z POSIX?

#!/usr/bin/env bash

set -o errexit
set -o pipefail
set -o nounset
# set -o xtrace

if ! command -v zpool &> /dev/null || ! command -v zfs &> /dev/null; then
    printf "ZFS binary does not exist. Exiting...\n"
    exit 1
fi

LOCK_FILE="/tmp/prepare_zfs.lock"

if [[ -f ${LOCK_FILE} ]]; then
    printf "Lock file already exists. Exiting...\n"
    exit 1
fi

touch "${LOCK_FILE}"
trap 'stty echo; rm -f "${LOCK_FILE}"; exit $?' INT TERM EXIT

while true; do
    read -rp "Enter disk device path: " DRIVE
    if [[ ! -b "${DRIVE}" ]]; then
        printf "Error: not a device.\n"
    else
        break
    fi
done

while true; do
    read -rp "Enter mount path (leave blank for /mnt): " MNT_PATH
    MNT_PATH=${MNT_PATH:-/mnt}
    if [[ ! -d "${MNT_PATH}" ]]; then
        printf "Error: not a directory.\n"
    elif [[ $(findmnt -M /mnt/"${MNT_PATH}") ]]; then
        printf "Error: already mounted.\n"
    else
        break
    fi
done

while true; do
    read -rp "Do you want to use encryption (answer y or n)? " ZFS_ENC_ENABLED
    if [[ ${ZFS_ENC_ENABLED} == "y" || ${ZFS_ENC_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

readonly ZFS_ENC_PASSWD="p"
readonly ZFS_ENC_KEYFILE="k"
if [[ "${ZFS_ENC_ENABLED}" ]]; then
    while true; do
        read -rp "Do you want to use (p)assword or generate (k)eyfile? " ZFS_ENC_TYPE
        if [[ "${ZFS_ENC_TYPE}" == "${ZFS_ENC_PASSWD}" || "${ZFS_ENC_TYPE}" == "${ZFS_ENC_KEYFILE}" ]]; then
            break
        fi
        printf "Error: invalid answer, valid choices are p and k.\n"
    done

    case ${ZFS_ENC_TYPE} in
        "${ZFS_ENC_PASSWD}")
            while true; do
                stty -echo
                read -rp "Password: " PASSWORD
                printf "\n"
                read -rp "Confirm password: " CONFIRM_PASSWORD
                printf "\n"
                stty echo
                if [[ "${PASSWORD}" != "${CONFIRM_PASSWORD}" ]]; then
                    printf "Error: passwords don't match.\n"
                else
                    break
                fi
            done
            ;;
        "${ZFS_ENC_KEYFILE}")
            ZFS_INSECURE_KEY="n"
            while true; do
                [[ "${ZFS_INSECURE_KEY}" == "y" ]] && break
                read -rp "Do you want to generate 128-bit, 192-bit or 256-bit keyfile? (default: 256) " ZFS_ENC_KEYLEN
                if [[ "${ZFS_ENC_KEYLEN}" == "128" ]]; then
                    while true; do
                        read -rp "Are you sure you want to use insecure key size (answer y or n)? " ZFS_INSECURE_KEY
                        if [[ ${ZFS_INSECURE_KEY} == "y" || ${ZFS_INSECURE_KEY} == "n" ]]; then
                            break
                        fi
                        printf "Error: invalid answer, valid choices are y and n.\n"
                    done
                elif [[ "${ZFS_INSECURE_KEY}" == "n" ]]; then
                    continue
                elif [[ "${ZFS_ENC_KEYLEN}" == "192" || "${ZFS_ENC_KEYLEN}" == "256" ]]; then
                    break
                else
                    printf "Error: invalid answer, valid answers are 128, 192 and 256.\n"
                fi
            done
            while true; do
                read -rp "Do you want to generate (h)ex or (r)aw keyfile? " ZFS_ENC_KEYTYPE
                if [[ "${ZFS_ENC_KEYTYPE}" == "h" || "${ZFS_ENC_KEYTYPE}" == "r" ]]; then
                    break
                else
                    printf "Error: invalid answer, valid answers are h and r.\n"
                fi
            done
            ;;
    esac
fi

read -rp "Enter zroot name (leave blank for zroot): " ZROOT
ZROOT=${ZROOT:-zroot}
read -rp "Enter username (leave blank for user): " USERNAME
USERNAME=${USERNAME:-user}

while true; do
    read -rp "Will you be using libvirt (answer y or n)? " LIBVIRT_ENABLED
    if [[ ${LIBVIRT_ENABLED} == "y" || ${LIBVIRT_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

while true; do
    read -rp "Will you be using LXC (answer y or n)? " LXC_ENABLED
    if [[ ${LXC_ENABLED} == "y" || ${LXC_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

while true; do
    read -rp "Will you be using LXD (answer y or n)? " LXD_ENABLED
    if [[ ${LXD_ENABLED} == "y" || ${LXD_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

while true; do
    read -rp "Will you be using Docker (answer y or n)? " DOCKER_ENABLED
    if [[ ${DOCKER_ENABLED} == "y" || ${DOCKER_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

while true; do
    read -rp "Will you be using NFS (answer y or n)? " NFS_ENABLED
    if [[ ${NFS_ENABLED} == "y" || ${NFS_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

while true; do
    read -rp "Will you be using systemd (answer y or n)? " SYSTEMD_ENABLED
    if [[ ${SYSTEMD_ENABLED} == "y" || ${SYSTEMD_ENABLED} == "n" ]]; then
        break
    fi
    printf "Error: invalid answer, valid choices are y and n.\n"
done

DISK_SECTOR_SIZE=$(lsblk -S -o PHY-SEC --raw --noheadings "${DRIVE}")
[[ "${DISK_SECTOR_SIZE}" == "512" ]] && ZPOOL_ASHIFT=9 || ZPOOL_ASHIFT=12
ZPOOL_ARGS="-f -o ashift=${ZPOOL_ASHIFT}           \
            -o cachefile=/etc/zfs/zpool.cache
            -O acltype=posixacl       \
            -O relatime=on            \
            -O xattr=sa               \
            -O dnodesize=legacy       \
            -O normalization=formD    \
            -O mountpoint=none        \
            -O canmount=off           \
            -O devices=off            \
            
            -R /mnt                   "

# zpool create -o ashift=12 -o cachefile=/etc/zfs/zpool.cache -m none -R "${MNT_PATH}" "${ZROOT}" "${DRIVE}"
# zfs create -o mountpoint=none -o com.sun:auto-snapshot=true -o compression=lz4 "${ZROOT}"/ROOT
# zfs create -o mountpoint=/ -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/default
# zfs create -o canmount=off -o mountpoint=/var -o com.sun:auto-snapshot=true -o xattr=sa "${ZROOT}"/ROOT/var
# zfs create -o canmount=off -o mountpoint=/var/lib -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/var/lib
# test "${LIBVIRT_ENABLED}" == "y" && zfs create -o mountpoint=/var/lib/libvirt -o com.sun:auto-snapshot=false "${ZROOT}"/ROOT/var/lib/libvirt
# test "${LXC_ENABLED}" == "y" && zfs create -o mountpoint=/var/lib/lxc -o com.sun:auto-snapshot=false "${ZROOT}"/ROOT/var/lib/lxc
# test "${DOCKER_ENABLED}" == "y" && zfs create -o mountpoint=/var/lib/docker -o com.sun:auto-snapshot=false "${ZROOT}"/ROOT/var/lib/docker
# test "${NFS_ENABLED}" == "y" && zfs create -o mountpoint=/var/lib/nfs -o com.sun:auto-snapshot=false "${ZROOT}"/ROOT/var/lib/nfs
# test "${SYSTEMD_ENABLED}" == "y" && zfs create -o canmount=off -o mountpoint=/var/lib/systemd -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/var/lib/systemd
# zfs create -o canmount=off -o mountpoint=/usr -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/usr
# zfs create -o mountpoint=/usr/local -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/usr/local
# zfs create -o mountpoint=/opt -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/opt
# test "${SYSTEMD_ENABLED}" == "y" && zfs create -o mountpoint=/var/lib/systemd/coredump -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/var/lib/systemd/coredump
# zfs create -o mountpoint=/var/log -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/var/log
# test "${SYSTEMD_ENABLED}" == "y" && zfs create -o acltype=posixacl -o mountpoint=/var/log/journal -o com.sun:auto-snapshot=true "${ZROOT}"/ROOT/var/log/journal
# zfs create -o mountpoint=/home -o com.sun:auto-snapshot=true "${ZROOT}"/home
# zfs create -o mountpoint=/root -o com.sun:auto-snapshot=true "${ZROOT}"/home/root
# zfs create -o mountpoint=/home/"${USERNAME}" -o com.sun:auto-snapshot=true "${ZROOT}"/home/"${USERNAME}"
# zpool set bootfs="${ZROOT}" "${ZROOT}"
# zfs set relatime=on "${ZROOT}"
# zfs set com.sun:auto-snapshot=true "${ZROOT}"
# zpool export "${ZROOT}"
# zpool import -o cachefile=/etc/zfs/zpool.cache -R "${MNT_PATH}" "${ZROOT}"

# clean up after yourself, and release your trap
rm -f "${LOCK_FILE}"
trap - INT TERM EXIT