Backup on encrypted lvm partitions with external HD

backup.sh

#!/bin/bash
#
# Credits go to
# http://earlruby.org/2010/02/adding-an-external-encrypted-drive-with-lvm-to-ubuntu-linux/

if [[ root != $(whoami) ]] ; then
    sudo $0 $@
    exit 0
fi

DISKID=$(find /dev/disk/by-id -name *WD_My_Book*part1)
DISK=$(readlink -e $DISKID)

LUKSNAME=crypt-backup-wd
VG=backup
LV=suse
MP=/mnt/backup

export BUPPATHS="/etc /home /opt /root /srv /usr/local"
export BUPINDEX=$MP/${LV}.bupindex
export BUPDIR=$MP/$LV

#function backup_setup() {
#    cryptsetup --verbose --verify-passphrase luksFormat $DISK
#    cryptsetup luksOpen $DISK $LUKSNAME
#
#    pvcreate /dev/mapper/$LUKSNAME
#    vgcreate $VG /dev/mapper/$LUKSNAME
#    lvcreate -L 1T -n $LV /dev/$VG
#    mkfs.ext4 /dev/$VG/$LV
#}

backup_mount() {
    cryptsetup luksOpen $DISK $LUKSNAME
    vgchange -ay $VG
    mount /dev/$VG/$LV $MP
    return $?
}

backup_umount() {
    sync
    umount /dev/$VG/$LV
    vgchange -an $VG
    cryptsetup luksClose $LUKSNAME
    return $?
}

ensure_mounted() {
    mount --fake /dev/$VG/$LV $MP >/dev/nul 2&>1
    [[ 0 = $? ]] && backup_mount
}

backup_bup_init() {
    ensure_mounted
    if [[ ! -d $BUPDIR ]] ; then
        mkdir -p $BUPDIR
    fi
    bup -d $BUPDIR init
    bup -d $BUPDIR index -uf $BUPINDEX $BUPPATHS
}

backup_print_modified() {
    ensure_mounted
    bup -d $BUPDIR index -vmf $BUPINDEX $BUPPATHS
}

backup_full() {
    ensure_mounted
    bup -d $BUPDIR index -uf $BUPINDEX $BUPPATHS
    bup -d $BUPDIR save -t -f $BUPINDEX $BUPPATHS
}

# ffbf4ea03f2ad9b41f71d7d8f748bdd667c19d15

backup_ftp() {
    ensure_mounted
    bup -d $BUPDIR ftp
}

backup_bupdir() {
    echo $BUPDIR
}

if [[ 0 = $# ]] ; then
    RUN="print_modified"
else
    RUN="$@"
fi

for cmd in $RUN; do
    backup_$cmd
    ret=$?
    if [[ ! 0 = $ret ]] ; then
        exit $ret
    fi
done

exit 0