An easy solution to automate backing up Raspberry Pi SD Cards to a writeable image while they are still running.
These images can be restored in the event of a card failure, meaning you don't have to go through all the hassle of installing and configuring everything from scratch!
Guide to usage here: https://blog.galt.me/automatic-raspberry-pi-backups/
Download the pibackup.sh file.
Make it executable.
Edit the file and replace the values of:
"backuppath=" and "daystokeep="
with your own location and days you wish to retain the backup images for.
Test run.
If it's working as expected automate with cron or systemd.