how do I check that two folders are the same in linux

Using diff with the recursive -r and quick -q option. It is the best and by far the fastest way to do this.

diff -r -q /path/to/dir1 /path/to/dir2

It won't tell you what the differences are (remove the -q option to see that), but it will very quickly tell you if all the files are the same.

If it shows no output, all the files are the same, otherwise it will list the files that are different.

If you were using scp, you could probably have used rsync.

rsync won't transfer files that are already up to date, so you can use it to verify a copy is current by simply running rsync again.

If you were doing something like this on the old host:

scp -r from/my/dir newhost:/to/new/dir

Then you could do something like

rsync -a --progress from/my/dir newhost:/to/new/dir

The '-a' is short for 'archive' which does a recursive copy and preserves permissions, ownerships etc. Check the man page for more info, as it can do a lot of clever things.

cd websitefind . -type f -print | sort | xargs sha1sum

will produce a list of checksums for the files. You can then diff those to see if there are any missing/added/different files.