zfsonusb

#!/bin/bash
# License: MIT
# Copyright (c) 2024 Salih Emin - SynergOps
# Origin: https://github.com/synergops/.zfsonusb

# Load configuration from external file
# shellcheck source=/dev/null
CONFIG_FILE=~/.zfsonusb.conf
if [[ -f "$CONFIG_FILE" ]]; then
    source "$CONFIG_FILE"
else
    echo "Configuration file $CONFIG_FILE not found!"
    exit 1
fi

VERSION="24.09.21"

# Function to list available disks in /dev/disk/by-id
list_disks() {
    echo -e "Listing available disks in /dev/disk/by-id:"
    for n in /dev/disk/by-id/*; do
        if [[ "$n" == *usb* ]]; then
            # Get the actual device (follow the symlink)
            DEVICE=$(readlink -f "$n")
            echo "$n ... points to -> $DEVICE"
        fi
    done
}

# Function to import the ZFS pool
import_pool() {
    IMPORT_CMD="sudo zpool import"
    for DISK in "${DISKS_ARRAY[@]}"; do
        IMPORT_CMD="$IMPORT_CMD -d $DISK"
    done
    IMPORT_CMD="$IMPORT_CMD $ZFS_POOL_NAME -N"
    echo "Importing ZFS pool $ZFS_POOL_NAME"
    eval "$IMPORT_CMD"
    sleep 1
    echo "Mounting non-encrypted ZFS datasets:"
    sudo zfs mount -a
    sleep 1
    # If you don't use NFS shares and you get an error about  
    # "failed to lock /etc/exports.d/zfs.exports" 
    # run "systemctl disable --now zfs-share.service"
    echo "----------------------------------------"
    echo "ZFS datasets mounted:"
    echo "----------------------------------------"
    sudo zfs get mounted
    echo "----------------------------------------"
    sleep 1
    echo "ZFS pool status:"
    echo "----------------------------------------"
    sudo zpool status
    sleep 1
    echo "----------------------------------------"
    echo "ZFS pool capacity status:"
    echo "----------------------------------------"
    sudo zpool list
}

# Function to export the ZFS pool and power off external disks
export_pool() {
    echo "Syncing filesystems..."
    sudo sync
    sleep 1
    echo "Unmounting ZFS datasets..."
    sudo zfs unmount -a
    sleep 1
    echo "Exporting ZFS pool $ZFS_POOL_NAME ..."
    sudo zpool export "$ZFS_POOL_NAME"
    sleep 1
    # Prepare the udisksctl power-off command
    POWER_OFF_CMD="sudo udisksctl power-off"
    if command -v udisksctl &> /dev/null; then
    	for DISK in "${DISKS_ARRAY[@]}"; do
    	     POWER_OFF_CMD="$POWER_OFF_CMD -b $DISK"
    	done
    	# Execute the udisksctl power-off command
        echo "Powering off external disks..."
    	eval "$POWER_OFF_CMD"
        sleep 1
    else
    	echo "udisksctl was not found in your system. Please install it or you have to manually poweroff your external disks"
    fi
}
backup_to_pool() {
    if command -v rsync &> /dev/null; then
        echo "Backing up $BACKUP_SOURCE to $BACKUP_DESTINATION"
        echo "Backup will log in file: /tmp/zfsonusb_backup.log"
        echo "Backup will exclude files in file: $BACKUP_EXCLUDE"
        sleep 2
        rsync --archive -hh --log-file=/tmp/zfsonusb_backup.log --delete-excluded --partial --info=stats1,progress2 --modify-window=1 --exclude-from="$BACKUP_EXCLUDE" "$BACKUP_SOURCE" "$BACKUP_DESTINATION"
    else
        echo "rsync was not found in your system. Please install it to use backup feature"
    fi
}

# Function to display help with detailed steps
show_help() {
    echo "zfsonusb v$VERSION"
    echo "Usage:" 
    echo "      zfsonusb {import|export|list|backup|help}"
    echo ""
    echo "Steps to use the script:"
    echo "  1. List available disks in /dev/disk/by-id:"
    echo "     zfsonusb list"
    echo ""
    echo "  2. After identifying the disks, edit the 'zfsonusb.conf' file"
    echo "     to include the disk paths under the DISKS array."
    echo ""
    echo "     Example 'zfsonusb.conf':"
    echo ""
    echo "     ZFS_POOL_NAME=\"zones\""
    echo "     DISKS=("
    echo "       \"/dev/disk/by-id/usb-ST950042_0AS_00A1234567C4-0:0-part1\""
    echo "       \"/dev/disk/by-id/usb-TOSHIBA_MQ01ABF050_00A1234567C4-0:1-part1\""
    echo "     )"
    echo ""
    echo "     Set the \"BACKUP_SOURCE\" and \"BACKUP_DESTINATION\" in the \".zfsonusb.conf\" file to the desired values."
    echo "     Edit the \".rsync-home-excludes.txt\" file to exclude the files and directories that you don't want to backup."
    echo "     All lines starting with a # are ignored by rsync, i.e. those directories will be backed up."
    echo ""
    echo "  3. After configuring the 'zfsonusb.conf' file, you can:"
    echo "     - Import the ZFS pool: zfsonusb import"
    echo "     - Export the ZFS pool and power off disks: zfsonusb export"
    echo ""
    echo "Options:"
    echo "  import   : Import the ZFS pool and mount datasets"
    echo "  export   : Unmount the ZFS pool and power off external disks"
    echo "  list     : List available disks in /dev/disk/by-id"
    echo "  backup   : Backup data to the ZFS pool"
    echo "  help     : Display this help message"
    echo ""
    echo "Backup Usage:"
    echo "  The backup feature uses rsync to backup data to the ZFS pool."
    echo "  If you need this feature, configure the following variables in $CONFIG_FILE:"
    echo "    BACKUP_SOURCE: The source directory to backup"
    echo "    BACKUP_DESTINATION: The destination directory in the ZFS pool"
    echo "    BACKUP_EXCLUDE: Path to a file containing rsync exclude patterns"
    echo ""
    echo "  The backup will log messages in a temporary file at: /tmp/zfsonusb_backup.log"
    echo "  CAUTION: Make sure you understand the rsync backup process and the configuration before running the backup."
    echo "           The backup will exclude files in $BACKUP_EXCLUDE"
    echo "           and delete files in $BACKUP_DESTINATION that no longer exist in $BACKUP_SOURCE"
    echo ""
}

# Command-line argument parsing
case "$1" in
    import)
        import_pool
        ;;
    export)
        export_pool
        ;;
    list)
        list_disks
        ;;
    backup)
        backup_to_pool
        ;;
    help|--help|-h)
        show_help
        ;;
    *)
        echo "Error: Invalid option"
        show_help
        exit 1
        ;;
esac