On Tue, Mar 26, 2013 at 08:39:33AM +1100, Hiddensoul (Mark Clohesy) wrote:
Yes that is correct, if you are taking files from the NAS then compressing them on your local machine then uncompressing them on the same local machine then putting them on the external USB drive, why compress/uncompress at all ?
At the end of the day you are still moving uncompressed data across the network so you are just adding extra steps with tar...
tar doesn't compress unless you tell it to with one of the compression options such as '-z' (gzip) or '-j' (bzip2). any recent GNU tar (i.e. from the last few years) has several compression options available, and '-I' if you need to tell it to use a particular program that doesn't have it's own specific option. for the initial copy, 'cp -af' or 'tar cf - ... | tar xf - ...' would be a reasonable choice. rsync wouldn't be bad either, but would use significantly more memory and CPU. follow up with a final rsync (or two or several dozen - once the bulk copy has been done you can keep rsyncing daily or whatever until you're ready) in short, it doesn't really matter what you use as long as the machine doing the copying has sufficient RAM and CPU power. craig -- craig sanders <cas@taz.net.au>