echo " -d, --device: specifies the output snapshot device (default: none)."
echo " -o, --output: specifies the output image file (default: $type dependent)."
echo " -r, --resync-string: internally used to resync previous made snapshots."
echo " -d, --device: specifies the output snapshot device (default: none)."
echo " -o, --output: specifies the output image file (default: $type dependent)."
echo " -r, --resync-string: internally used to resync previous made snapshots."