there is not longer needed the manualy created blacklist of copied files;
also no need to remove symlinks from clone subdir

use "tar --checkpoint-action=exec="echo -n \".\"" instead of
"awk '{ ORS=\"\" ; if (++nlines\%50 == 0) printf \".\"; fflush() }'";
we are interested into the return code from tar, e.g. not-enough disk space