Support native GNU tar incremental backups instead of using --newer.

[backup.sh] / backup.sh

diff --git a/backup.sh b/backup.sh
index 366978dd0bfebe73a9021eeecb607af8631fc7a1..e7c04c0f9b06183156dbf798fc8638278b80e7a4 100755 (executable)
--- a/backup.sh
+++ b/backup.sh
@@ -77,38 +77,58 @@ backup()
  echo -n `date` >&2
  printf " $computer: $computer:$filesystem $backuplevel backup\n" >&2
 
- if [ "$backuplevel" = "daglig" ] || [ "$backuplevel" = "incremental" ]
+ SNARFILE="${storagedir}/${computer}/${sfilesystem}/.incremental.snar"
+ incrementalsnar="/root/.backup/${sfilesystem}.snar"
+ if [ "$backuplevel" = "daglig" ]
  then
-  lastd=`cat ../.date`
-  lastcmd="--newer='$lastd'"
+   # If incremental backup, we need to copy the incremental status to $computer.
+   # If it does not exist, whine a bit and then run date-based instead.
+   if [ -s "$SNARFILE" ]; then
+     if ! scp $SNARFILE root@$computer:$incrementalsnar; then
+       echo `date`" $computer: Could not copy .incremental.snar to $computer"
+       die
+     fi
+     lastcmd="--listed-incremental=$incrementalsnar --no-check-device"
+   else
+     echo `date`" $computer: Missing incremental.snar for $filesystem, doing date-based backup instead until next full backup" >&2
+     incrementalsnar=""
+     lastd=`cat ../.date`
+     lastcmd="--newer='$lastd'"
+   fi
  else
-  lastcmd=""
+    lastcmd="--listed-incremental=$incrementalsnar"
  fi
 
  # expand the exclude-path for use with tar
  exf=`ssh root@$computer "ls ~/.backup/exclude"`
 
  # We try to run tar on the remote computer
- #    z gzip it
  #    c create archive
  #    C change to directory first
  #    . where to start taring (see C)
  #    $lastcmd only files newer than this
  #    --one-file-system don't traverse file systems
+ #    --use-compress-program compress it using gzip or pigz
  #    --exclude-from file to get exclusion pattern from
  #    Pipe the stuff over ssh to ourselves, run pee to cat the contents to a
  #    file and build a file list, respectivly.  
  TARFILE=$DATE.tmp
- TARCMD="ssh root@$computer \"nice -n 19 ionice -c3 tar --one-file-system -zcf - -C $filesystem . $lastcmd \
+ TARCMD="ssh root@$computer \"nice -n 19 ionice -c3 tar --one-file-system --use-compress-program $compressor -cf - -C $filesystem . $lastcmd \
        --exclude-from=$exf\" | pee \"cat > $TARFILE\" \"tar tzvf -\""
  echo `date`" $computer: Running $TARCMD" >&2
  eval $TARCMD > $DATE.idx
 
- if [ -s $TARFILE ]; then
-  # File is >0 in size, we assume it worked.
+ if [ $? -eq 0 ] && [ -s $TARFILE ]; then
+  # File is >0 in size and neither cat or tar tzvf failed; we assume it worked.
+
+  if ! scp root@$computer:$incrementalsnar $SNARFILE.tmp; then
+    echo `date`" $computer: Could not copy .incremental.snar from $computer"
+    die
+  fi
 
   # Move tar file in place
   mv $TARFILE $DATE.tgz
+  mv $SNARFILE.tmp $SNARFILE
 
   # Update timestamp
   echo $DATEs > ../.date && touch -t $DATE ../.date
@@ -156,6 +176,14 @@ backup()
   # We don't want to return 0
   die
  fi
+
+ # Check if pigz is available
+ if ssh -n root@$computer "pigz -V 2>/dev/null"; then
+   compressor=pigz
+ else
+   echo `date`" $computer: pigz missing; falling back to gzip."
+   compressor=gzip
+ fi
  
  filesystems=""