Strategy 3 – making SD card backups

Git and SFTP are great for keeping code safe, but they don't help you reinstall and reconfigure Raspbian on a card. The procedures for Windows, Linux, and Mac are quite different for this. The basic idea is to insert the SD card and use a tool to clone the whole card to a file known as an image, which you can restore with Etcher when you need recovery. Warning: you should restore images to cards of the same size or larger. First, properly shut down your Raspberry Pi, take its SD card, and put that into your computer. These clean images are large so do not put them in your Git repository. It's beyond the scope of this chapter, but I recommend finding a way to compress these files as they are mostly empty right now. In all cases, expect this operation to take 20-30 minutes due to the image sizes.

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