OK, I symlinked the logger of the rescue system with logmsg, so now I have logging to /var/log/messages enabled but this didn't help me any further.
Here my steps so far:
chmod 755 restore
ln -s /bin/logger /usr/bin/logmsg
chmod 755 /usr/bin/logmsg
Output of /var/log/messages:
Jul 25 19:26:52 rescue root: enumerate_disks
Jul 25 19:26:52 rescue root: hda
Jul 25 19:26:52 rescue root: DISKS=1
Jul 25 19:26:52 rescue root: Partitioning /dev/hda...
Jul 25 19:26:52 rescue root: Old partition table for /dev/hda:
Jul 25 19:26:52 rescue root: parted -s -- /dev/hda mklabel msdos || shellout
As far as I could see, the script still was't trying to restore the image and I didn't no why. It stops around here:
DISK_SIZE=`parted -s $DISK0 unit MB print | grep 'Disk geometry for' | sed 's/^.*-//g' | sed 's/\..*$//' | sed 's/MB//' `
[ -z $DISK_SIZE ] && shellout
As I had a closer look to the parted params I found out that the version of the rescue system doesn't support "unit MB" for parted. So I simply deleted it because it uses MB as standard unit.
Now it seems to work. At lease it is running...