backup/lvm

   1 #!/bin/bash
   2 # invoked by backup scripts as
   3 #    lvm snap $vardir $device $mountpoint
   4 #               creates and mounts on $vardir/snap-mount
   5 #               creates $vardir/snap-device -> device
   6 #    lvm drop $vardir
   7
   8 set -e
   9 snapkind=lvm
  10 . /usr/share/chiark-backup/snap-common
  11
  12 #---------- clean up anything
  13
  14 lvmdropcore
  15
  16 if test "$opmode" = drop; then
  17         echo 'lvm snap dropped'
  18         exit 0
  19 fi
  20
  21 #---------- create snapshot
  22
  23 fstype="$(mount | sed -n \
  24  "s,^$device on $mountpoint type \([a-z0-9][a-z0-9]*\) .*,-t \1 ,p")"
  25
  26 lvmunmapperdevice
  27 lvmdevice2vgroup
  28
  29 if [ -z "$lvm_lvsize_opts" ]; then
  30         lvmextentscore1
  31
  32         lvdisplay_out="$(really lvdisplay -c "$device")"
  33         extents2="$(printf "%s" "$lvdisplay_out" | awk -F: '{print $8}')"
  34         extents2=$(( $extents2 + ($extents2+9)/10 - 1 ))
  35
  36         lvmextentscore2
  37 fi
  38
  39 lvmcreatecore1
  40
  41 lvcreate -s \
  42         $lvm_lvtools_opts \
  43         $lvm_lvsize_opts \
  44         -n $lvm_lv \
  45         $lvm_lvcreate_opts "$device" $lvm_lvcreate_args
  46
  47 mkdir -- "$snmnt"
  48 mount -v -r $fstype $lvm_mount_opts "$lvpath" "$snmnt"
  49
  50 echo 'lvm snap activated'