rpi-clone is a shell script that will back up (clone using dd and rsync) a running Raspberry Pi file system to a destination SD card (via a USB card reader) or USB disk 'sdN' plugged into a Pi USB port
I use it to maintain backups of several Pi SD cards I have and the destination backup SD cards/USB disks can be a different size (smaller or larger) than the booted SD card or USB disk. rpi-clone works on Raspberry Pi distributions which have a VFAT boot partition 1 and a Linux root partition 2. Tested on Raspbian but should work on other distributions which have this same two partition structure. rpi-clone does not work with NOOBS.
rpi-clone can clone the running system to a new SD card/USB disk or can incrementally rsync to existing backup Raspberry Pi disks. During the clone to new disks, rpi-clone gives you the opportunity to give a label name to the partition 2 so you can keep track of which disks have been backed up. Just stick a correspondingly named sticky label on each disk you have and you can look up the last clone date for that backup in the rpi-clone log file /var/log/rpi-clone. My convention is to name 8GB SD cards: SD-RPI-8A, SD-RPI-8B, ... and similarly, 4GB cards: SD-RPI-4A, ...
If the destination disk has an existing partition 1 and partition 2 matching the running partition types, rpi-clone assumes (unless using the -f option) that the destination is an existing backup with the partitions properly sized and set up for a Raspberry Pi. All that is needed is to mount the partitions and rsync them to the running system.
If these partitions are not found (or -f), then rpi-clone will ask if it is OK to initialize the destination disk partitions. This is done by a partial 'dd' from the running booted device /dev/mmcblk0 (or /dev/sd? for a USB boot) to the destination disk /dev/sdN followed by a fdisk resize and mkfs.ext4 of /dev/sdN partition 2. This creates a completed partition 1 containing all boot files and an empty but properly sized partition 2 rootfs. The destination partitions are then mounted on /mnt/clone and rsynced to the running system.
You should avoid running other disk writing programs when running rpi-clone, but I find rpi-clone works fine when I run it from a terminal window. However I usually do quit my browser first because a browser can be writing many temporary files.
rpi-clone must be run as root and you must have the rsync program installed.
rpi-clone will not cross filesystem boundaries by default - this is normally desirable. If you wish to include your mounted drive(s) in the clone, use the -c switch. But use this option with caution since any disk mounted under /mnt or /media will be included in the clone.
After rpi-clone is finished with the clone it pauses and asks for confirmation before unmounting the cloned to SD card/USB disk. This is so you can go look at the clone results or make any custom final adjustments if needed. For example, I have a couple of Raspberry Pis and I use one as a master. When I clone for the benefit of the second Pi, I do a "cd /mnt/clone/etc" and fix the files needed to customize for the second Pi (well, actually I do that with a script that takes my desired Pi hostname as an argument). Either way, you typically might need to change at least these files:
/etc/hostname # I have one of rpi0, rpi0, ...
/etc/hosts # The localhost line should probably be changed
/etc/network/interfaces # If you need to set up a static IP or alias
If you cd into the /mnt/clone/tree to make some of these customizations or just to look around, don't forget to cd out of the /mnt/clone tree before telling rpi-clone to unmount.
rpi-clone is on github, to get it and install it to /usr/local/sbin: Go to https://github.com/billw2/rpi-clone and download the zip file:
$ unzip rpi-clone-master.zip
$ cd rpi-clone-master
$ cp rpi-clone /usr/local/sbin
or, use git to clone the repository:
$ git clone https://github.com/billw2/rpi-clone.git
$ cd rpi-clone
$ cp rpi-clone /usr/local/sbin
For a French translation of rpi-clone by Mehdi HAMIDA, go to: https://github.com/idem2lyon/rpi-clone
GTR2Fan on the Pi forums has instructions for putting rpi-clone into the menu of the desktop GUI: https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=137693&p=914109#p914109
Bill Wilson billw--at--gkrellm.net