Linux – How to copy directory from one Linux server to another with a minimum in-between period

I'm not sure I understand what you're trying to do, but you could create gzipped backups on the main server making sure that they're readily rsyncable and not bother decompressing anything in transit.

gzip(1)

--rsyncable
       While compressing, synchronize the output occasionally based on
       the  input.   This  increases  size by less than 1 percent most
       cases, but means that the rsync(1) program can much more  effi‐
       ciently  synchronize  files  compressed with this flag.  gunzip
       cannot tell the difference between a  compressed  file  created
       with this option, and one created without it.

Sneakernet Anyone?

Assuming this is a one time copy, I don't suppose its possible to just copy the file to a CD (or other media) and overnight it to the destination is there?

That might actually be your fastest option as a file transfer of that size, over that connection, might not copy correctly... in which case you get to start all over again.

rsync

My second choice/attempt would be rsync as it detects failed transfers, partial transfers, etc. and can pick up from where it left off.

rsync --progress file1 file2 user@remotemachine:/destination/directory

The --progress flag will give you some feedback instead of just sitting there and leaving you to second guess yourself. :-)

Vuze (bittorrent)

Third choice would probably be to try and use Vuze as a torrent server and then have your remote location use a standard bitorrent client to download it. I know of others who have done this but you know... by the time they got it all set up running, etc... I could have overnighted the data...

Depends on your situation I guess.

Good luck!

UPDATE:

You know, I got thinking about your problem a little more. Why does the file have to be a single huge tarball? Tar is perfectly capable of splitting large files into smaller ones (to span media for example) so why not split that huge tarball into more managable pieces and then transfer the pieces over instead?