DeltaCopy is an open source, fast incremental backup program. Let's say you have to backup one file that is 500 MB every night. A normal file copy would copy the entire file even if a few bytes have changed. DeltaCopy, on the other hand, would only copy the part of file that has actually been modified. This reduces the data transfer to just a small fraction of 500 MB saving time and network bandwidth.

DeltaCopy is a "Windows Friendly" wrapper around the Rsync program, currently maintained by Wayne Davison. "rsync" is primarily designed for Unix/Linux/BSD systems. Although ports are available for Windows, they typically require downloading Cygwin libraries and manual configuration.

http://www.aboutmyip.com/AboutMyXApp/DeltaCopy.jsp

Old thread but great suggestion. The Windows world has been missing the benefits of rsync for much too long.

The program itself is GPL'd and seems to work fine. Although the client component might be portable, the server portion wants to register with system services, which seems unlikely to qualify.

Its unfortunate there are so many programs here on the site that feature some type of copy mechanism that's faster than Window's default when there are tools like rsync-based DeltaCopy. Obviously a 100 gig file with only a few kilobytes of changes should take an instant to transfer, not minutes. If anyone knows of a program that will compare contents of individual files and update only the changes, please post.

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After a number of recent backups that too unnecessarily long for only a (statistically) tiny number of changes, I decided to go back and make a real go of this. Unfortunately, my results were less than encouraging.

DeltaCopy Server - Dserver.exe - Added a new item, put in a folder, gave it a username and password. Unfortunately the insists on running as a windows service on the server computer. Checked the "local server" option and then ran server.

DeltaCopy Client - DeltaC.exe - Created a new profile, put in the IP address of the server (it didn't recognize my windows host name), but nothing seemed to work. Works with Window's own scheduling, so not much chance of this even being sort of portable. I figured out after some wrangling to get it to use a manual mode, but at this point it was beyond complicated.

Anyway, after a lot more testing I had to discard this program. Just couldn't get it to work. Even tried the QtdSync program with DeltaCopy's server without success.

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