How can I easily confirm in Linux that two separate directories have the exact same contents?

CentOS 5.x

Mq question seemed similar to this one but I wasn't sure...

I have two servers (completely isolated from each other), each with a directory and sub-directories that should have the same exact contents.

For example the directory layout could be something like:

SERVER A -

/opt/foo/foob/1092380298309128301283/123.txt
/opt/foo/foob/5094380298309128301283/456.txt
/opt/foo/foob/5092380298309128301283/789.txt
/opt/foo/foob/1592380298309128301283/abc.txt

SERVER B -

/opt/foo/foob/1092380298309128301283/123.txt
/opt/foo/foob/5094380298309128301283/456.txt
/opt/foo/foob/5092380298309128301283/789.txt
/opt/foo/foob/1592380298309128301283/abc.txt

Ideally I'd like a way to do a recursive check and have something confirm that everything matches.

I also want to avoid using any third-party tools.

Any ideas?

One good way is to use md5sums on every file in the tree:

Run this on server1:

find /opt/foo/foob/ -type f -print0 | xargs -0 md5sum > report_from_server1.tx

Run this on server2

find /opt/foo/foob/ -type f -print0 | xargs -0 md5sum > report_from_server2.tx

Then just compare the two files (using diff) or whatever you like.

Is that along the lines of what you're looking for?

Of course, you can use SSH to just execute the command remotely if you want.

If you don't necessarily care about what changed, just that something has changed, rsync is still really good for that. Try running this command and take a gander at the output, assuming this is run from 'servera'.

rsync -avcn /opt/foo/ serverb:/opt/foo

The resulting list will be those files that would have been modified if you actually ran the sync process. Keeping in mind that the files will show up in the list even if only the timestamp changed, but the contents remained the same. Since we added the -n flag, then no actions will actually be performed, only reported.