ClonePi will clone a running Raspberry Pi to a target SD card, device or file.
Features:
<ul><li>Works with standard 2-partition Raspbian setups, multi-partition NOOBS setups and more</li>
<li>On-the-fly incremental cloning</li>
<li>Clone to a physical device and optionally increase or decrease the size to fit the target disk.</li>
<li>Clone a file (stored on a NAS or external disk) and optionally compress it.</li>
<li>Configuration options allow you to adjust it to work with many systems.</li>
<li>Script links allow to extend it beyond the default use cases.</li>
<li>Headless operation, works without GUI</li>
<li>Raspbian is tested; can be modified to work with other systems.</li>
</ul>
https://github.com/SpoddyCoder/clonepi