Given are two directories a/ and b/ with apparently equal content,
$ diff -Naur a b
$
After packing the contents of contents of the directories in to tars,
cd a/ && tar cf ../a.tar * && cd ..
cd b/ && tar cf ../b.tar * && cd ..
I noticed that the checksum of those are not equal,
$ md5sum *.tar
9cf2799bab8a0ac7cbeabee5f2305f17 a.tar
4104addd5c8c31b23179cf23fc15a578 b.tar
Note that this is even without using gzip which is known to have time-dependent meta data.
Doing the same thing a second time
cd a/ && tar cf ../a2.tar * && cd ..
cd b/ && tar cf ../b2.tar * && cd ..
yields the same checksums
$ md5sum *2.tar
9cf2799bab8a0ac7cbeabee5f2305f17 a2.tar
4104addd5c8c31b23179cf23fc15a578 b2.tar
so tar time stamps have nothing to do with it. Apparently, the contents of the folders are not entirely equal, although diff says so.
Can that be?
