I have a 1 TB internal drive that has two 1/2 TB partitions, one for Windows and the other for Ubuntu 14.04 LTS. The station has become primarily a Linux station and I never boot into Windows anymore.
I wanted to create an image backup so I used DD to clone the internal drive to an external 1 TB USB drive. Unfortunately the USB drive appears to be just a few Gigabytes shy of the internal drive and DD ended with a "Not enough space on drive" error message. Now I am seeing something odd. When I ejected the USB drive and plugged it back in, I see two 1/2 GB partitions that appear to be duplicates. They have identical GUID's and Nautilus shows identical directory structures and content. I'm guessing that something about the incomplete copy of one of the partitions has left the external drive in a broken state.
How can I use DD to just clone the Linux partition to the external drive? That's all I really want.