chiark - git - mdw - rsync-backup/blob - create-backup-volume

   1 #! /bin/sh -ex
   2
   3 : ${vgtag=@backup} ${vgprefix=vg-backup-}
   4 : ${mntbkpdir=/mnt/bkp}
   5 : ${STOREDIR=$mntbkpdir/store} ${METADIR=$mntbkpdir/meta}
   6 : ${RANDOM=/dev/random}
   7
   8 case $# in
   9   2) tag=$1 pv=$2 ;;
  10   *) echo >&2 "usage: $0 TAG PV" ;;
  11 esac
  12 vg=$vgprefix$tag
  13
  14 vgcreate --addtag $vgtag $vg $pv
  15
  16 lvcreate -L64M -nmeta $vg
  17 mkfs -text3 -Lmeta /dev/$vg/meta
  18 mount /dev/$vg/meta $METADIR
  19
  20 echo $tag >$METADIR/volume
  21 dd if=$RANDOM bs=1 count=512 |
  22         cryptop encrypt backup >$METADIR/crypt.blob
  23
  24 lvcreate -l100%FREE -ncrypt $vg
  25 cryptop decrypt backup <$METADIR/crypt.blob |
  26         cryptsetup luksFormat \
  27           --cipher=twofish-xts-benbi:sha256 \
  28           --hash=sha256 --key-size=256 \
  29           /dev/$vg/crypt -
  30
  31 cryptop decrypt backup <$METADIR/crypt.blob |
  32         cryptsetup luksOpen --key-file=- /dev/$vg/crypt cbackup
  33
  34 mkfs -text3 -Lbackup /dev/mapper/cbackup
  35
  36 mount /dev/mapper/cbackup $STOREDIR
  37 touch $STOREDIR/.rsync-backup-store