A few remarks:
1. Don't pass a directory and all it's subdirectories to "tar". If you give it the (top-level) directory to archive, then it'll go through all files/subdirectories recursively.
So, in your case, you only need to do:
Code:
tar -cvf 123.tar 123/
2. If you only want empty directories (so bare directory tree), without any regular files, you first need to either remove all regular files (ie run "find 123 -type f -exec rm {} \;" ) or to create a copy of your directory structure (without copying the files). The latter can be done for instance by running:
Code:
find 123 -type d -exec mkdir /new/path/{} \;
tar -cvf 123.tar /new/path/123/
Check your results via a "tar -tvf 123.tar".