rpi-clone is a shell script for cloning a running Raspberry Pi booted source disk (SD card or USB disk) to a destination disk which will be bootable.

Destinations include:

• SD cards in the SD card slot or a USB card reader
• USB flash drives
• USB hard drives and SSDs
• NVMe drives attached directly to the Pi PCIe bus

Install rpi-clone:

curl https://raw.githubusercontent.com/geerlingguy/rpi-clone/master/install | sudo bash

If booting off an internal microSD card, clone to an external USB drive:

sudo rpi-clone sda

If booting off an external USB drive, clone to the internal microSD card:

sudo rpi-clone mmcblk0

If booting off an internal microSD card, clone to a PCIe NVMe SSD (note: you may need to change EEPROM settings to boot off NVMe SSDs):

sudo rpi-clone nvme0n1

For an exhaustive list of options and usage scenarios, read this project’s README.