I’ve mentioned a few times lately that I’m working on my backup plan for GNU/Linux. I started by looking at great free software tools like Samba’s rsync and GNU Tar, and I don’t think I need to look much further than them. There is also GNU Cpio, which I haven’t really investigated yet.

I may have more to say later about my rsync and tar adventures, but for today here’s something I came up with to emulate a feature of a tool I had in Windows that I couldn’t find how to do with existing tools in GNU. The xcopy DOS command lets you recursively copy files modified after a certain date by using the /D:date option.

your questions:

Why would you want to do this? Well, one reason would be for offsite backups. I regularly store backup discs in a bank safe deposit box. I then occasionally want to copy changed files from the last dropoff, encrypt them, and send to my gmail account or carry around on a USB thumb drive. I’d like to have a lightweight way to do this that didn’t rely on a system of incremental backups.

Doesn’t tar take care of this with the --after-date option? Yes, but...

More Here.