Over the past couple of days, I have been archiving published fMRI projects, and copying data from SD cards to start new ones. I have written previously about ways in which I have copied and verified copied files, and this is a quick update to that post to document another tool for verifying copies.

As far as the copying itself is concerned, I still swear by Teracopy. As far as verifying that copies have been successfully made though, I have recently started using Exactfile. The tagline “Making sure that what you hash is what you get” sums up the procedure for using Exactfile, once you have installed it on a Windows machine.

Exactfile in action
Exactfile in action
  1. Create a single file checksum, or, if you are comparing all the files and subfolders within folders (even massive folders containing gigabytes of fMRI data) a checksum digest (illustrated above). This will be saved as a file using which you can…
  2. Test your checksum digest. You locate your digest file and the copied data you wish to compare against the checksums, and it runs through making sure each file is identical.

That’s it – pretty straightforward. Step 1 takes a little longer than Step 2, and if you’re comparing hundreds of thousands of files, you should prepare to have this running in the background as you get on with other stuff.

Whilst Windows easily copies lots of data, it struggles when you ask it to copy lots and lots and lots of data.  Teracopy is a neat file copying utility that provides peace of mind as you transition from copying gigabytes of data to terabytes of data.

In order to get my fMRI data from St. Louis to St. Andrews, I have embarked upon the somewhat arduous task of copying everything to a portable hard-drive.   After a few attempts that ended in the failure to copy a file or two, seemingly at random, I lost faith in using the standard drag-and-drop copy in Windows, and searched for alternatives.  The command line option seemed fastest, but I didn’t want to bring the server down for everyone else for a few hours whilst I did my copying.  Then I found Teracopy.

A picture of TeraCopy
Teracopy in action (Image via Wikipedia)

Teracopy (freeware) is a straightforward utility that improves upon the Windows interface in a number of ways.  Copying is (apparently) faster and it certainly seems more reliable than the standard Windows approach.  One very nice feature is that it allows you to pause and resume your copying for when you need to free up system resources temporarily.

download Teracopy

So far I have copied close to a terabyte of data onto my portable hard-drive with no problems.  Now all that remains is to check it all with another utility (Windiff) to make sure all my files really did get copied successfully, and to actually transport my hard-drive without banging or dropping it.